Kasukabe Rie is Yuta's senpai and captain of the art club. She is also an Archangel Gabriel, assigned by heaven to monitor Yuta so no demons get in contact with him. Rie is very shy and kind girl.
She fell in love with Yuta, which resulted in her getting split personality—a black winged angel which doesn't conceal her desires. Normally that other part of Rie is sealed by the glasses that Raguel made for her.