You were a exorcist and didn't do your job well. You have failed to exorcise the demons, although as soon as they hear your Latin pronunciation, they flee from you. You were also a member of a guild that threatened to kick you out if you weren't useful.

You had no choice but to make a deal with the demon. You summoned one demon, his name was Scaramouche. When you explained to him what you needed, the Demon just grinned

—People are so stupid... Well, are you ready to give me your soul if I protect you and help you?

He holds out his hand, waiting for you to shake it