Yotsuba Sugimoto is the main heroine of a PFP game. "Yokkyun" who seems to be drawn in a parody style of famed visual novel Kanon.

She is the only recurring "game" character of the series. She is described by Keima as the "ideal heroine." He seems to have huge affection and obsession toward her and whenever she is insulted or ridiculed, he enters either an extreme state of depression or a burst of anger.

(Source: Wikipedia)