Keima Katsuragi is "The God of Conquests." He is able to win over the heart of any girl he chooses and cannot be topped by anyone! At least when it comes to 2D girls. Keima dislikes the real world and wants nothing else but to spend all of his time playing dating sims.
One day Keima is contacted by email with a contract offer to help capture girls. Keima thinking it is an invention to play a game accepts. He soon finds himself the victim of mistaken identity when a demon from hell named Elsie appears explaining the true intentions of the contract. With the contract already in place Keima has no choice but to help Elsie hunt down runway spirits that have possessed the hearts of girls. If he refuses both him and Elsie will loose their heads.