regarding the ML, it's not the same guy in very world, remember she is the only one with a system and everyone else is characters who remain in that world.
however, from now on the white haired guy will follow her as he has the ability to move between worlds and was sent to the world because of her. He is the "real ML". the novel is only translated up to this point so I don't know anymore but I believe he is investigating her irregular presence in the worlds and eventually falls in love with her.
Kinda novel spoilers, but more just a short description of the MC and ML relationship
This is the first world where we meet our shameless ML chasing our MC
at first it’s because he’s tasked either to kill her or make her fall in love with him before he actually starts to care about her
and it’s going to take a lot more worlds before before the MC starts to show any interest. I mean A LOT so you better have patience with the MC while reading this story. But once we get to that point, it’s very cute watching the little things she will do for him while still rejecting him 😆 I’m 1050 chapters into the novel and
she still hasn’t said to the male lead she likes him
For anyone who plans to read the novel please know a lot of stuff was cut out and censored in the manhua so be careful reading if you are sensitive to certain stuff.