i like thinking of Ooi as Tsundere more then Yandere. They kinda went overboard with it. Anime's making her character even worse.
I can't help but feel some of the staff are trying too hard to make nods to the Fandom. Like they saw how the fandom loved making Ooi into a raging lesbian(which admittedly we do joke about) and that some of them just went to Pixiv and were like "This must be what they all want! Make sure Anime Ooi is Ripe with the stench of bitches and all that jazz!"
The crazy lesbian doesn't always have to be yandere. At least I think Ooi is more like Kuroko in Toaru series.
The worst part about the anime depiction is about her trying to lock up Kitakami for herself to keep her untouched by others, being highly territorial, and her way of looking others like an androgynist seeing men as trash. That and her voice feels somewhat off for the character.