Engage Kiss

Bayron City, an artificial island located in the Pacific Ocean near Japan, whose economy relies on the extraction of Orgonium, a new energy source, is troubled by the mysterious appearance of demons. To conceal their existence from the public, the city government hires PMCs that combat and neutralize demon-like monsters. One such PMC called "I&S Office" is ran by the protagonist, Shu Ogata. Differing from other PMCs, Shu's only employee is a demon girl named Kisara. Kisara has the appearance of a young girl despite being hundreds of years old, and her combat strength is highly rated. Though Shu does little work and is constantly in need of money, Kisara seems affectionate for him and toils to support him. Despite Shu's close ties to Kisara, he frequently contacts his ex-girlfriend Ayano Yugiri for help. Ayano and Shu used to work for the same PMC called "AAA Defender Co." until their breakup and Shu's departure from AAA. Ayano claims that their relationship has ended, yet she still acquiesces to Shu's pleas for help. Shu appears to be a loser whose livelihood depends on his relationships with two women. However, he has an ambitious goal: to uncover the truth behind a demon-related incident long ago in which his parents and sister went missing.