Hello (Rom-Com) World summary:

In front of the shy, book-loving Naomi Katagaki, one day appeared ‘his future self’, NAOMI KATAGAKI. His goal was to make Naomi his classmate’s, Ruri Ichigyou’s, boyfriend, and rewrite the tragic fate of Ruri...

However!
Starting from the next page, it’s a spin-off manga about a possible ‘world’!!
Some characters may be a bit different, so don’t worry about reading it!!