I have a friend who's like Kasane-- but I wouldn't call her a womanizer? It's more like she just has a momentary obsession with someone/something and just gives all her undivided attention to that person/thing; gradually the excitement wanes and the feeling of obsession fades and she moves on. I can understand from the subject how it could feel like leading them on, but it's more like an intense focus rather than a wine and dine lovebombing type of situation?
Anyhow, I feel bad for Mimei because I'm normally on the side of the childhood best friend unrequited love tropes, but I can't help be interested in Meguru and her backstory. I'm not sure if anything will come out of fruition from this story since Meguru is clearly a minor and the MC is held back by morals and ethics lol. I should also note that we don't know if Kasane ever meant to approach Mimei or her other "obsessions" with a romantic light, the same way she does with Meguru.