I Was Traded by Death

Due to my decadence, I smoked and drank all day long, and went to bed late and got up late. I was informed by the God of Death that I was going to burp. I begged hard, and the God of Death agreed to make an agreement with me, using other people's lifespans to extend my time. And gave me a super power, and from then on I became his tool... What is his purpose? Where should I go from here? This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.