In Search of purpose throughout different worlds

A man named kijin kairi suffered from cancer, his days were spent taking medicines and in a hospital bed. He knew that his life was short. But he wanted to live, at the same time, his life was coming to an end. But contrary to his expectations, he was granted another chance at life by so called "sponsors", he was pushed into a world of demons and Superhumans with nothing but himself and his memories. Watch him find his own self and purpose in a foreign world. ___________________ I do not own demon slayer or anything related to the story expect for my oc _____________ it's a multiverse fanfic. first world is demon slayer. second is jjk. _____________________ This is my first time writing something, if you don't like it, feel free to criticize it, I will try to improve as much as I can. Point out any mistakes or plot hole that you notice. thanks