Stray Incubus

In a conflict between the races, a group of brave warriors supported by the gods purge a dark race of demons from existence. But due to the mercy of one warrior, one demon child is spared as she decides not only to spare him, but also to take him with her and raise him. A few years later, the incubus grows into an adult and wishes to set off in an adventure.

[From Itch.io]