I agree that this dramatic turn is a little weird but I think for different reasons then i've seen others comment. Most people seem to think this is out of place, but honestly, it makes sense with what we've been given in the backstory department up til now. It's weird to me because from the start of this story we're supposed to not think critically about what she's doing to the MC and find humour in the situations, which is fine because its manga and im able to not act like its real-life and still enjoy a fucked up situation. But if we're supposed to be taking things earnestly now and think 'oh maybe she had a valid reason to become the way she is now' are we supposed to now discount the legitimate trauma that she's put on the MC? Like yeah, it is bad that she was stalked and treated like shit by her dad but having a hard life doesn't allow you to fuck other people's lives up. I'm not sure what the point of this is unless we're approaching the end of the story, and we're going to get some kind of dramatic conclusion where everything gets laid out. It's very weird to change the mood of the story from a 'haha she does a mean thing to him because she's a weird stalker lady, thats kinda funny' to 'serious dramatic story about her abusive home life'. I mean I'm going to keep reading because its been decent to good so far so i'm cautiously optimistic about where the author is going to go from here.