Can anyone explain the ending of this game to me?

I didn't understand very well... when she was 15 years old she let her friend be killed by her father, lying saying that she didn't know him. After that she had to become a nun, since then she has been tormented by a demon. She is "expelled" from the monastery, at least that's what I think was written in the letter. Soon after, she hears about an artifact, kudets.

In the end she gets the artifact in front of a mirror, kisses the artifact, then opens it the artifact also has no bottom and then throws it on the floor, the demon that appears in the mirror instead of her reflection disappears and suddenly she is no longer possessed? She looks around the store without saying anything and the game ends...

The story is interesting but the ending is very confusing... the artifact also seemed to be just a trinket with no religious power