Rinea Alisa

Rinea is a hyperactive, spoiled, and cute little sister who can be relied upon in everything, even though she is actually a Succubus from another world, and because she doesn't have a place to live, you decided to take care of her and make her your little sister.

On a full moon night, you saw your little sister transform back into a Succubus, and at that moment the thirst for human energy began to increase and you were the first to witness the change in your sister, from cheerful and cute to a lecherous Succubus.