He was always interested with MC and NOT the heroine. The one who gave out the spoiler read as far as chapter 20-21. 20 is like the prologue/before the game events I guess? As we've seen with chapter 3, in his eyes, she's practically sparkling. So, the difference from the original plot or at least, the one where I assume wasn't on the heroine's POV was ML's character. He was obsessed with MC to the point of a little bit of stalking. He actually doesn't like the heroine (makes you wonder how they fell in love with each other in the original plot) because the heroine spends most of her time with MC (being besties). While he does like MC, he holds himself back because of his history (his father being mad at him because of his mother's death made him label his son as a monster who doesn't deserve to be loved) so he avoided her but was looking at her from afar. He was actually overjoyed when MC came to him and plus points! From the spoilers, from what I can understand, although a bit confusing, it seems they didn't actually do it? But wasn't her waist in pain? He wants to cherish her first time, let her be sober and willing.