Yume Nikki is a strange, unknown game, with no dialogue and a unique art style, so of course, the fans created many theories, some good, some bad, some complex, some that make us lulz. This article will categorize the theories by character. There will then by long theories with contributions from most characters, making a huge orgy of wild mass guessing.
NOTE: NOT EVERYBODY BELIEVES YUME NIKKI HAS A STORYLINE, AND MANY PEOPLE BELIEVE KIKIYAMA JUST MADE THIS GAME FOR THE LULZ. KEEP THIS IN MIND, THESE ARE ALL FAN THEORIES, AND THE ONLY KNOWN "OFFICIAL" STORYLINE IT WHAT WE CAN SEE IN THE GAME, LIKE MADOTSUKI'S NAME.
Madotsuki
Madostuki was raped
Whether you like it or not, their is much evidence that Mado was raped. In the Forest World, along a strange road, several creatures in the background with eyes watch over you. The last one's eyes follow you for a split second as you leave. Many claim these are ovaries, which adds "sexual content" to the game. Some say that KyuuKyuu-Kun, a large colorful pole thingy, rubbing another pole, is phallic imagery (A rainbow thing with a face rubbing a pole? Thats not innuendo at all!). The Knife and Cat Effects alter the speed of which Kyu-Kyu rubs the rail of the staircase, speeding it up or down. Full-screen events feature an event called FACE, which is achieved by going through a door right next to Kyu-Kyu. Some say it resembles the head of... well, you know. This is those people's main evidence of Mado getting raped/molested.
Madostuki lives in an apocalyptic world.
Madostuki seems like a perfectly normal girl, albeit possibly being a hikkikomori. Yet her dreams are strangely terrifying and eccentric, and she acts like she has been there before, displaying almost no emotion. That combined with the fact that her apartment is the only one in view, and she wont leave, and her TV doesn't get any channels, and her only source of entertainment is a NES game, it would seem that whatever is out there is worse than what is in her dreams. (Half-Life 2 anyone?)
Madostuki is a transgender
She hates her penis, and wants ovaries. Nuff' said.
Poniko
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