Ao is a gloomy and introverted high school boy who hates himself and has no friends... What brings Ao joy is watching "MagicalRhythm", a children anime. Naru, the most popular boy in his class, approaches Ao when he sees his MagicalRhythm keychain.
Ao becomes attached to Naru, his first "friend", someone who shares his interests and is also kind and gentle.
As things progress Naru starts to have a twisted affection towards Ao...
Regardless how painful, difficult, disgusting or wrong the extension of friendship may be, "Even so, we're still friends, right?"