Ah, yes, another power fantasy self-insert. It's quite dogshit, ainnit?
2~3 generations' worth of lives spent and he's acting like a naive boy. He mentioned something about people with bad intentions approaching him most of the time in his previous life but he's acting clueless as fuck.
The...
To the people wondering why the ending feel rushed, it's because the author is having family issues which forces her to put an indefinite hold on her career as a mangaka so that she could move out of Tokyo and back to her family.