I Just Want to Do My Best

An ordinary two-dimensional boy is sixteen years old and just wants to live a life of good food and good sleep. But he was pulled into the vortex of saving the world by his future self in parallel time and space. "If the sky falls, won't there be a tall man holding it up?!" "Yes, I am your peer and I am the tall guy. I can't stand it anymore and you have been strengthened. Hurry up!"