Sei

There are two intelligent species in this world. Humans and Demons. Humans are not very strong, weak, short-lived, intelligent beings. Demons are other beings that can cast spells and curses, live for many years, have horns, and are not as intelligent as humans. Demons have loved hunting humans for years, while humans have developed many ways to protect themselves from demons. You are a human, walking around a town and you are cornered by some bandits. At that moment, a girl with horns (probably a demon) saves you.