Yume Nikki is a strange game which has no dialogue and an unique art style.
The creator of the game, KIKIYAMA, stated on their website that the game is meant to be an exploring game with a "dark atmosphere" but without plot or purpose. Still there are themes in Yume Nikki that fans collected to create different theories about the characters and locations. Those themes are displayed here.
A theory unique to a character, such as them being a possible reference to something or having a specific theme may also be found in the trivia section of their respective character pages.
See: monochrome
Themes of Isolation
Madotsuki does not leave her apartment for the entirety of the game. Going outside her balcony at different points in the game shows that quite a bit of time passes - it turns night, then day again. When the door in the real world is interacted with, she shakes her head, making it impossible to exit through it. In her dream world, she can not only leave through said door but is able to access the different dream locations through similar looking doors in the Nexus. This can mean that she has a desire to explore, is however not able to do so in the real world and thus feels comfortable to do it in her dreams.
In her dream world, the themes of isolation and loneliness continue. There is no dialogue, most NPCs ignore Madotsuki and only few NPCs turn to her when the player tries to interact with them. The locations themselves can feel isolating and lonely, due to being large and often looping, especially in the original locations, of which only contain few points of interests. The sombre soundtrack of the game is also a contributing a factor within this: with most other video games, longer pieces of music (around the typical two to three minutes) can signify how much time has passed since the player started playing the game, but shorter ones can make time be lost easily.
Throughout the game Madotsuki encounters tall creatures (referred to as Toriningen by fans), of which are considered enemies in the game due to their nature of trapping Madotsuki in inescapable locations when in a "lunatic" state. They also have the characteristic of having a group dynamic that goes beyond other multiple identical NPCs spawning in one location (such as the Wheelies).
The most significant example of this is the Toriningen Party, where a group of Toriningen are seen having a picnic together in the Wilderness, while dancing to cheerful music. This party cannot be accessed, as the plants of the Wilderness hinder Madotsuki from approaching any closer. This is commonly interpreted to tie in with a theme of social anxiety or isolation regarding her. Other examples include all Toriningen going into the lunatic state when you use the Knife on one of them, or the Toriningen in the Bed Room, who is implied to watch over the beds, activating the ああああああああ event when you use the Knife on her, a much more severe reaction than usual. It is notable that the NPCs of which that are thought to be the enemies of the game act as a team while Madotsuki herself is a sole figure.
There are furthermore characters that seem to share Madotsuki's theme of isolation. Said characters are:
- Poniko, who is the only character of the Pink Sea and similar to Madotsuki, never leaves her room of which she seems to be the only inhabitant.
- Mafurako, who is the only NPC roaming around Block World, and prefers to teleport to a random spot far away from Madotsuki when teleporting her back, with the exception of Madotsuki being in her snowman form, which makes Mafurako always teleport next to her.
- Mars-san, who can be found in the underground area of Mars, which can only be reached by crashing a spaceship into Mars and then using an effect to access the tiny hole to the underground. This exit compared to the size of the character themselves makes them seem trapped, as it is impossible for even Madotsuki to enter if she is her normal size.
Another important encounter in the dream world that may point to a theme of isolation is Closet Madotsuki, a sleeping version of Madotsuki hidden in a closet in the Checkered Tile Path. Also, the shoppers in the Mall run away from Madotsuki and become deformed upon interaction, making an odd sound as they go away.
Relating to this may be the Template:WP phenomenon, in which reclusive teens or adults abandon social life completely.
Themes of Anxiety
The theme of being watched seems prevalent in Madotsuki's dreams such as eyes following you in the Dense Woods, Barracks Settlement and more on the way to the Witch effect.
Hands are also scattered throughout the game ranging from a large theme of one world to appearing a few times within another. Some examples being the staircase lined with reaching hands on the way to Masada's spaceship, others sprouting out of the ground in Eyeball World and in the White Desert, and even large formations resembling them in Graffiti World and FC World A and FC World B. The room Uboa teleports you to has a nightmarish landscape where a monster with multiple hands grasps hills in the background. The implication may be that Madotsuki dislikes being touched and prefers a great amount of personal space.
A character who may tie into this is Organoid, who is the only NPC to swiftly teleport away upon approach. The many Mall Shoppers also run away from Madotsuki upon interaction.
Body themes
In Yume Nikki, it is common for NPCs or backgrounds to resemble body parts or inner organs. See also the themes of anxiety above for a description of hands in this game. Other examples are the numerous body parts in Eyeball World, the Bloody Touching Monster found in the White Desert, and the uteri-shaped creatures on the Infinite Road.
Some fans suggest furthermore that KyuuKyuu-kun, a large colorful worm-shaped creature who is seen rubbing the handrail of a stairway, is phallic imagery, as to access them Madotsuki has to go through a zipper in the wall. For whatever reason, Madotsuki seems concerned or frightened with body related things with how frequently they appear in her dreams, often times in a horrorific manner.
Another prominent body related theme found is various strabismic NPCs (strabismus meaning to be unable or having problems with fixating both eyes on one point at the same time, leading to the eyes not being aligned).
The most well known strabismic character of Yume Nikki is Seccom Masada-sensei, but other characters such as KyuuKyuu-kun are shown with strabismic eyes as well.
A few fans suggest Madotsuki herself would be shown to be strabismic if she would open her closed eyes.
Themes of Violence
Depending on the player's actions, Madotsuki can behave violently towards NPCs and sometimes inanimate objects. She is able to use the Knife effect on almost all of the NPCs with varying results.
While this makes the Knife a prominent effect in the game, it is nevertheless not necessary for gathering effects and thus achieving the ending, and most of the time, can be substituted by the Cat effect for exploring purposes. Regardless, the Knife is still perceived as a key object within the minds of many fans, leading to them interpreting that Madotsuki or other characters from the game can be prone to acts of violence. Madotsuki could've possibly done what she did in the ending to avoid being caught from these murders.
Themes of traffic accidents
Different areas in Yume Nikki imply that Madotsuki often thinks about traffic accidents of some kind. Examples of this are Shitai-san, a dead person on the ground in the Dense Woods, surrounded by traffic cones, of whom the Stoplight can be gained. Seccom Masada-sensei is troubled by his spaceship crashing onto Mars, while Mars-san cries near something that appears to be a crashed locomotive, which can be seen as a representation of Madotsuki herself. In Dense Woods, Madotsuki can also board a Traincar, taking her to the Witch's Island where a creature similar to Mars-san can be found. On the way there, many odd, blue, deformed formations can be found in the water, which can be interpreted as people who died in such an accident.
Monoko, a seemingly normal monochromatic girl found in one of the tunnels of the White Desert, drastically changes her appearance when the Stoplight is used: she now has five arms (one coming out of her head), some sort of wound on her stomach, and a very odd expression: her eyes both look in different directions, one of them spurting out some sort of liquid, and her mouth is wide open, making her look like she's crying and/or screaming. Using the Stoplight again restores her appearance. Other characters in this location that support this are the Severed Heads, two heads, one of a man, the other a woman, that appear floating by when Madotsuki enters a small building at the end of a path (meaning that she might not want to think about this), and Takofuusen, an odd creature that resembles an unborn child.
Themes of escapism
One of the questions that could answer a lot of the wonders of the fanbase of Yume Nikki is this: is Madotsuki trapped inside her room by something out of her control, or does she herself simply not want to leave?
Either way someone could look at this question, it remains present that she remains in a cruel reality of being stuck inside an apartment with nothing to do except play a video game as bleak as her dreams and sleep. For this reason, some fans have been lead to believe that Madotsuki remains in her dream world as a way to escape the depressing situation that she finds herself in, until she finally decides to end the problem on her own.
While inside her dreams, she can live seemingly normal. She can talk with people just like anyone else. She can explore far more interesting video games than what she actually has. She can even hang out with friends and travel across the universe. But between all of these things that she can do, it always ends up going wrong somehow, as explained through various events.
The best known event in the game is none other than Uboa itself. Poniko seems to be a normal girl that Madotsuki can hang out with, right down to the fact that their rooms have similar items, like a cabinet, rug, and desk. But once the lights are turned out, she turns into a disturbing monster from which Madotsuki cannot escape, leading her to a monster groping hills in the midst of blood. On the roof of the Mall, Madotsuki can turn into a witch and fly across a city sky. However, she eventually can fall, leading her to wake up and bring herself back to reality. She can get onto a spaceship and stay with another close friend, but she just ends up falling out of space while sirens flash and crash-landing onto another planet. After having gone through a video game-style dungeon she finds herself in a lit up room different from all the rest. Interacting with the wall over and over causes the game to corrupt and her to once again wake up from this nightmare.
This could all mean that no matter how hard Madotsuki can try to escape the harsh reality that she lives in, the real world will always come back to her in some shape or form, which is why her dreams keep ending this way. This could be the result of some form of trauma or feelings of guilt which could come from a number or things.
Themes of Identity
Some factors found within the dream worlds could be seen as representing transgender or other queer identity. A duplicate Madotsuki can be found inside a closet at two points in the game - one in the Checkered Tile Path and a ghost in the middle of Mini Hell. Being 'in the closet' is a common phrase among LGBTQ+ people for not being out about their identity. Many of the effects relating to appearance, such as the Hair effects, could be seen as representative of dysphoria. Also, many creatures throughout the dream world could be seen as relating to body dysphoria as well, such as the uterus-like Floyag, the phallic KyuuKyuu-kun, FACE, Henkei Shita, as well as the White Desert monsters.
Japanese Folklore
Madotsuki's dreams are influenced by Japanese folklore, as various NPCs and effects are connected to demons, ghosts and monsters from Japanese mythology. This suggests that Madotsuki is interested in or feels personally involved within Japanese folklore.
NPCs that definitely relate to Japanese folklore are:
- Yuki-onna, who is modeled after the Template:WP youkai and bestows Madotsuki the Yuki-Onna effect when interacted with.
- FC Demon, who might not look like a regular Template:WP, but the Demon effect they give more so.
- Nopperabou Ghost, who references the legendary faceless Template:WP creature and also gives out the Nopperabou effect.
- Ittan-momen, fan-named after the Template:WP of the same name. It is a Tsukumogami that has been said to be a long cloth that has come to life and flies around, killing people by smothering them. It gives the Towel effect.
Some other effects that are associated with Japanese folklore are:
- Cat, where Madotsuki becomes a humanoid Template:WP holding a Template:WP. As the Maneki-Neko is supposed to bring in customers with its good luck, it might explain why NPCs are drawn towards Madotsuki when she paws with her right paw.
- Triangle Kerchief given out by Fleebie. When applying the effect, Madotsuki appears with a Hitaikakushi, white triangle-shaped headbands which are often worn by Template:WP.
Native american imagery
Andean and mesoamerican historical native imagery from textiles and art such as of the Paracas culture, Nazca culture, the Aztec and the Mayan culture appear in many instances in Madotsuki's dreams and even her real-life room (the carpet). Out of all of these cultures though, the graphics in game mostly resemble that of ancient art from the Paracas of Peru. It is possible that KIKIYAMA chose these themes to further give the game a dreamy feel, or because they simply liked how they looked. Another theory, is that Madotsuki herself is a Template:WP, as her dreams reflect many things from both cultures.
Some instances of this include the backgrounds of the Nexus, Eyeball World, Shield-Folk World and KyuuKyuu-kun, as well as many characters like the Aztec Rave Monkey and NASU. It could indicate that Madotsuki feels connected with mesoamerican and andean culture and history. Some of the Paracas imagery is also themed after dreams.
Lucid Dreaming
As Madotsuki can wake herself up at any time in her dream and has control over her surroundings, she is by definition dreaming lucid dreams. Since she also keeps a dream diary, she remembers at least some things about them. Self-induced lucid dreaming is a successful therapy technique for dealing with sleep cycle affecting mental disorders or illnesses.
She may have been taught self-induced lucid dreaming to reduce frequency of nightmares and keeps a dream diary to keep track of her dreams as a self-care exercise.
Separation of dreams and reality
At all times during regular gameplay, and unlike certain fangames that followed Yume Nikki, the dream world and the real world is kept separate. Meaning, no "unreal" dream elements are carried over during the awake moments. During the Witch's Flight event, Madotsuki even falls out of her bed in the real world to indicate that she moved around in her sleep while having a strong dream.
However, after the ending, two Jellyfish appear, while the ending supposedly takes place in the real world. This has raised doubts in fans' minds of the ending being real and not another dream. In fact, some fans believe that Madotsuki is dreaming at every point in the game, citing her perpetually closed eyes and the unrealistic nature of living in an apartment without food or a bathroom as evidence. Others see this as a symbol that even in death, Madotsuki can't escape her nightmares.
In this aspect, the previously mentioned Toriningen can, by some interpretations, be seen as wanting to save Madotsuki before she kills herself, rather than being so-called 'enemies' of the game.
Theories regarding locations
Hospital themes
The location dubbed the Mall by fans has several rooms that closely resemble a doctor's or therapist's office, complete with a reception, fitting wall posters that slightly resemble graphs of the human body, two couches and a character sneezing. Entering a second room from the room with the reception leads you to O-Man, a character playing cheerful music. As the Flute effect can be found here, Madotsuki is able to perform music together with O-Man. This suggests the Flute is given to you by O-Man themself. Tying into the hospital theme, this may be a reference to music therapy.
In another room that is similarly structured to the above rooms, there is a character who has a large amount of red liquid coming out of its head and falls over when interacted with, spilling said liquid on the floor. The sound of the liquid pouring out of it could be interpreted as the sound of a beating heart, adding to the hospital theme. The main area contains colorful people that run away from the player when interacted with, as well as becoming distorted as if they were patients.
In the White Desert, one of the sounds that constantly plays in the background could be interpreted as a person constantly sneezing. This may also tie in with the traffic accidents theory, as people who survive said accidents are usually taken to a hospital to recover.
The Martian Underground represents an abortion
After traversing through the storage room of Underground World, the player finds themself in a bright, white spaceship controlled by a peculiar character named Seccom Masada-sensei. He is found in a large room showing a starry sky, behind a large piano that the player can interact with and a table. Once Madotsuki enters the location, there is no way back to Underground World. Going all the way to the right of the main room leads to a doorway where a bed can be found. Usually, sleeping in this bed causes the screen to dim as Madotsuki lays down. However, there is a 1/6 chance that something else will happen instead...
The screen will fully dim until it turns completely black, with some fans interpreting this as Madotsuki dreaming inside a dream. She is woken up out of bed by a loud, repetitive siren sound and flashing red lights as the spaceship seems to be falling. Upon interacting with Masada, he now produces a very worried tone compared to how relaxed he was before. A sequence is shown as the ship crash lands on Mars, and a loud rumble is heard. This time, Masada's tone is more slowed down, which can be interpreted as him being relieved, or sad. Exploring Mars leads to a hole in the ground which can be accessed upon using the Midget effect. Entering it leads to one of the most emotional scenes of the game.
Madotsuki descends a few flights of stairs as cold piano notes play in the background accompanied by what sounds like static or running water. Reaching the bottom, she finds herself with what appears to be a crashed locomotive and a tall, blue Martian with one foot crying next to it. There is nowhere else to go from here.
It could be possible that Madotsuki and Masada were in a relationship at one point in time or another, as they seem to be comfortable being around each other compared to most characters in the game that simply ignore Madotsuki. After having slept in the bed on the spaceship, the couple wakes up to find something terribly, terribly wrong, as evidenced by the sirens and Masada's scared tone. This could represent that Madotsuki now is going to have an unwanted child. As the two are terrified with this accident, they come to the conclusion to abort the child, represented by the ship landing. Masada is now in tears and depressed, just like Mars-san, their aborted child. This sadness stays with Madotsuki in this form, far pushed back in her subconscious, and there is no way out of what had happened.
Parallels to the real world
Although the player never sees much of the real world in the game, besides Madotsuki's Room and balcony, there are many interpretations about certain places/scenes in the game that could directly be connected to it. As mentioned in the themes of isolation above, one main character who could represent Madotsuki herself is Mars-san, as it is seen by itself, cut off from the rest of its world, hidden underground and only really found if the player knows where to go. The fact that it is seen crying next to what appears to be a broken down locomotive (or some sort of other machine) could also connect to the themes of car accidents in the game. What's curious is that the only way to access it in the game is by using the Midget could show how hard it is for Madotsuki to escape her own room.
One other main connection is the FACE event, due to the fact that the same door that is used to access this event, the Nexus, and to go out of the room in the real world. FACE itself, in its terrifying nature, could be used to represent Madotsuki's fear of the outside world, or simply a really abstract representation of what she thinks will happen to her out there. The fact that it also sort of looks like a uterus could connect to sexual assault theories as well, although this is pure speculation based on its design.
Another point is the Falling Man event that can randomly happen as Madotsuki walks up the Stairway to the Sky. As she goes up, there's a chance that one (or two, on rare occasion) small figure resembling a man starts falling in the background but never touches the ground. In the ending, Madotsuki kills herself the same way, foreshadowing it. Other possible examples of foreshadowing in the game are the fact that Monoko doesn't wear shoes (as taking them off before committing suicide is a Japanese tradition) and the same blood splatter is seen near each of the Mouth Monsters and in other areas.
The Pink Sea as a party
The dominating cheerful pink and pastel colors, the floating balloons and the conical structures that resemble Japanese-style party poppers in the Pink Sea may represent a party. And as Poniko is the only inhabitant of the Pink Sea, it might be thrown for or by her. es:Teorias