The old man is named Beelze and his Bronzong is named Hellbell.
Beelze is a gentleman,he acts very kind and understanding at first but once you continue interacting with him things start to get creepy...
Beelze will use Hellbell to do a cursed sounding ring incredibly loudly if you don't follow his orders sometimes.
After a while of knowing Beelze he will ask you to sign a contract,it seems like an innocent one but once you sign it,your free will is his..