Chaos;Head is a visual novel in which the player takes the role of Takumi Nishijou, an otaku and borderline shut-in, who experiences delusions. The game is mostly linear, but frequently includes player choices: the player is able to choose whether Takumi should experience a positive delusion, a negative one, or if he should manage to stay grounded in reality. Positive delusions involve seeing comical or erotic scenes, while negative ones include graphic violence or other horror elements. The player chooses the delusions through the "delusional trigger" system: a green and a red light are displayed on the top of the screen, representing positive and negative delusions, respectively. Source: Wikipedia, "[en.wikipedia.org/wiki/Chaos%3BHead Chaos;Head]", available under the CC-BY-SA License.