Wat. My speculation isnt as tragical as yours though. But yeah. Hinata is 100% yandere.
Ah sorry, my bad. I referred that to the part where you wrote about Hinata's mother raping the guy. In such a scenario she was an extremely bad example and Hinata was maybe even born from that incident. If she knows then she would not feel well and view her blood as contaminated and herself as bad because she will remind everyone of the incident through her very existance. Another idea would be her mother stealing Hinata-kun's sperm when he donated it at the Fertility center, maybe even committing other crimes in the process. Also not a nice setting.
That said, I would like to know more about Hinata's background and we might see something as a follow-up from this feeding episode when Hinata has to come clean to her friends Kana and Miku at least...
But my assumption is more towards neglect and being a very bad example for Hinata that she fears herself being no different from the mother.
Yeah, that isn't as horrible, yes, but from Hinata's perspective it's a bad thing either way, no matter the reason. I do feel sorry for her to have that kind of past.
It was so out of the character for him.
Given how he acted so far, yes, this one is an outlier. But maybe the mayhem now is necessary for Kanaria to rise and shine her brightest. Or for Miku to show her power for once. Not just the goofy side. We will know, hopefully soon.