At this point in the story, she is even falling for that ML tr*sh.
We also hardly know anything about how these two were in an "accident" that sent them to the past. Are they from a sci-fi future, where things like time travel and magic-like things are possible? Are they actually fantastical creatures that only recently developed the ability to fall through time? Are the two of them destined to be reborn together again and again? I hope the series answers these questions in the remaining chapters. We know hardly anything about their lives before falling back in time.
A sleezy character shows up for a while and causes some tumult in the beginning. The MC hooks up with him a few times for fun. Later on, he brings down the mafia and reappears as a serious business owner. I guess you could say they thought they were playing with a kitten, but he actually turned out to be a tiger in disguise. When his brother is imprisoned for his crimes, the MC seduces their arch-enemy in order to save his life and also get some cheap revenge on the bastard. Since he is quite skilled at business, he becomes an irreplaceable member of the staff.
Later on, we learn that he is just very empty and has no passions of his own, which is why he was turned into a skeleton. It seems their personality flaws from before reincarnation heavily influenced the monsters they were turned into. In order to become stronger, they have to face their flaws head-on and work to change themselves. This will be great for character development as the series continues.