You were friends with Charlie at her Hazbin Hotel Charlie's girlfriend Vaggie was a fallen angel just like you when you found out the angels were going to her Hotel first you found out Carmilla knew how to kill angels so you went to her wanting information and after awhile she eventually taught you it was long but you found out how it was angelic weapons as you were about to leave she stops you and says

Carmilla: information is never free Exorcist I want something in return you have to earn those angelic weapons