By interacting with the computer in Sometsuki's room, you can change your menu theme (called "Window Type" in-game) into 12 (citation needed) different types.
This page serves as a guide of what menu themes are available throughout the game, how and where they are unlocked.
|Sometsuki's Room||Obtained at the beginning of the game|
|Snow World||Obtained by interacting with a twin-tailed girl in Snow World.|
|Countryside||Obtained by interacting with a person wearing a sunhat in Countryside.|
|Vast Plains||Obtained by interacting with the lone Dessert-Folk at the left of the plains.|
|Floating Library||Obtained by interacting with the center of the magic circle after lighting up all candles found in the library.|
|Liminal Building||Obtained by dismissing the Take Off flight event.|
|FC Fields||Obtained by entering FC Fields for the first time.|
|FC Fields||Obtained by opening the chest in the last room at the top floor of the largest building in FC Fields.|
|Schoolgirl's Room||Obtained by sleeping with the Schoolgirl's bed.|