My Lovey-Dovey Demon Final by ebi-hime - Adult Sex Game

Taiki is your average guy. He’s nineteen years old, in his first year of university, and he’s just starting to learn what it means to be an adult.
During the summer vacation, Taiki goes to the countryside to stay with his grandparents alongside his siblings: the haughty, fashionable Chiharu; the tom***ish troublemaker Nene; and the sweet, shy Reza.