アンジエリカ

A very gentle, motherly  and innocent sister.  She is praised as Our Lady by the believers who attend church.  She treats believers mercifully even if they are perverts like  the protagonist. But the reality is that she is a devil who is being punished for mischief by adhering to faith. Even if she tries to do evil deeds, she will always end up doing good deeds, etc. Her libido, which was suppressed, can be awakened by the spellbook, and she seems to transform into a dirty horny devil after that.