Koakuma Teeri to Kyuuseishu!?

A boy named Souichiro takes in a young girl with pink hair and unusual clothing after meeting her on a rainy day. Despite her odd appearance, she seems ordinary except for the black wing growing from her back. She identifies as a devil and says she has nowhere else to go, so Souichiro allows her to stay. The next day, a blonde girl claiming to be an angel arrives at his home. She tells Souichiro he has the potential to become either a "Savior" or a "Super Villain." The story involves a romantic comedy featuring Souichiro, the devil girl, and the angel girl.