Likable characters and engage story

The story follows a man in his late 20's who is an Otaku introvert type working at a bad company and one evening relaxing with his friend he sees rarely, he discovers something tragic happened to his childhood crush and regrets not doing anything. He then finds himself dead as well and time leaps to his first year of highschool before all this happened.

Can he change things around can he save the girl he loves from despair and suicide. Watch as a lead who tries his best and is brave to safeguard his future and unite with the girl of his dreams. Let's prevent the messy future.

On a Side not I also like the side characters and their developments. Our male lead has 2 male friends and the female lead has 2 as well. I hope we get to see their perspective in the future in some interludes or something.