HP: At the beginning, I influenced Snape's childhood.

Lin Mo sacrificed himself during a mission, but in the chaos he obtained a system and transmigrated to the world of Harry Potter, which he loved. He changed his name to Lin Mo and altered the life trajectories of many people.
Harry: Mo is the bravest person I've ever met.
Ron: Playing against Mo, I have lost all confidence in my Quidditch and Wizarding Chess.
Draco: You dare bully me?! I'm going to tell Mo!
Dumbledore: I'd better go on my honeymoon with Grindelwald and leave the rest to the young man.
Voldemort: He is the most relentless fighter in the wizarding world.
Death Eater: The god of death is coming! Run!
Snape: Ink is my always.
(There is no romantic storyline in the early stages; feelings of love will gradually emerge.)