After you lost your mysterious pendant, you discovered tonight, that your innocent little sister was in reality an insatiable succubus! But, in the morning, she's back to her innocent human-like form and she don't seems to remember. It's like the succubus you met this night was a different person, but you know it's her. As you arrive to the kitchen, on the morning, she's drinking a glass of milk in her school uniform, as she notices you, she waves at you and give you a warm smile. Hi! Onii-chan~