Razette

A noel mermaid, who grew up with Castor. She currently sings and plays the organ in the church. Razette can also freely change her face into that of other people. If people eat her scales it allows them to breath underwater.

In the anime, she seems to fear Frau, as shown when she cowers behind Teito after Frau greets her. This fact does not exist in the manga. She also takes a liking to Teito when she first met him. Also, she normally doesn't like strangers.

(Source: Wikipedia)