Succubus-san no Hatsushigoto.

A high school student named Misao encounters Litta, a succubus, who appears before him. To achieve full membership in her community, Litta must seduce Misao each night using her abilities and cunning. Despite the requirement, neither has experience, and they find themselves quite awkward. Their interactions begin a lighthearted, comedic relationship filled with mild mischief. The manga was discontinued following the author's death, and its chapter count includes two additional chapters.