Infinite Time Travel, I Fight the BOSS for the Protagonist

I was reading comics and listening to songs, and suddenly I traveled through time! The usual otaku came to countless different worlds. I heard that you have never lost against waves? Let you try what a rail gun is! Wow, with such strong muscles, I can knock him down with one punch! "Who are you?!" The villain was shocked. I took out a comic book. I am the protagonist of this comic! This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.