Kurorou Toriyama is a melancholic boy who is a member of an anime association. During a certain event, he spots Reiko, the student council president, wearing a costume.
Kokurou takes a picture of her, and using it as leverage he coerces Reiko into sexual disgrace wearing various costumes.

Furthermore, Midori from the association catches him in the act, so he rapes her and takes a picture of her, too.
Though the heroines are coerced into the disgraceful conduct by blackmail, they eventually learn to enjoy it.
Today is another day filled with new costumes which will invariable be soaked in white fluid.