Futsuu to Bakemono

Ito-san is a girl with a communication disorder, who longs to be "normal." She has a crush on her classmate Takahashi-san, who is reserved but gets along with everyone. One day, however, Ito discovers Takahashi's true identity! Takahashi-san is actually a monster who hides by mimicking human beings. Ito decides to learn how to act like a "normal" human being from the monster girl Takahashi. Will these girls ever be be able to fit in?

(Source: ComicWalker, translated)