She was pobably a Yandere since the begining but acted like a Tsundere because she thought they were blood related so she kept her distance between them but when she found out they weren't related the Yandere came out.
Well... I'm just going to go right ahead and say it. This is indeed based and if I dare say furthermore, which for what it's worth, I do in fact dare, quite redpilled as well.
@ArisenDresden True, if he didn't look like a loaf of bread dumped into water and then left to dry on the sun then childhood friend would just be a bitch.
@aodpds711 The houses being big implies that mc and his family is loaded plus the mc's grandmother was more subsurvient to her daughter than the other way around so my guess is that the mother inherited their wealth from her father while the mc's grandmother married into the family the same...