It's clear to me that what's happening is that Ibu does genuinely have feelings for the MC, and I bet she was tricked into screwing the MC over because of some 'charm' her jackass friends told her about back in Elementary School (and she's just a massive, gullible idiot that can't read the mood), which led to a TON of miscommunications between them, and this will end with them all becoming friends because 'lol, it was just a misunderstanding, bro'. It's pretty predictable, tbh.