Girl Inside The Dream

A mysterious girl with very long red hair whom Clavis meets in his dreams. She is quite playful and likes puns. However, her puns are extremely cold.

Spoiler

Her true identity is Fallen Angel Seraphi. (熾天使セラフィ)
Human Name: Stephanie Ranclay (ステファ＝ランクレー), usually just called "Stepha"