I want to reread a Quick Transmigration or a world hopping novel. In this novel, the ML for every world are the same (one soul). I've read it last year and can't remember much. In the first arc, I do remember that the ML first saw the FMC when she was singing in front of a crowd. The ML got attracted to her voice, then contacted her to sing to him so he could sleep. Then, the trait I remember about the MC is that she's pretty cruel. Whenever the ML (no matter which world) pushes her away or do anything bad to her, she will make him miserable despite having feelings for him. So, after a few worlds, the ML gained an instinct about not doing anything that would hurt the MC even though he doesn't remember her.
I think it's Transmigrated Canon Fodder Please Calm Down? I'm not sure because I didn't finish it. Though, I think you just gave me a spoiler