PT 1: Devil, which might hit one of those. His tragic backstory is, uh, not those, but he did kill his father and that can absolutely be classed as vengeance due to being unfairly wronged (child abuse based on him looking like his mother). He also hates/wants vengeance against someone else from his own world, but it's not as strong as it could be bc they finally fought again (it's also not as weak as it could be bc said person killed the shit out of Froud and didn't go the route he wanted) - also that one was definitely a fair wrong, so. He's also theoretically good at emotional honesty with himself, but he's garbage at recognizing emotions that fall under the category of grief/sadness/trauma/etc so there's also that.

PT 2: Froud used to be a serial killer when he was human, and genuinely thought until like, a couple months back, that people generally enjoyed dying. As in, that it made them happy. This is something he's thought for probably thousands of years. He's done things like extort villages into giving him human (...well, ribika) sacrifices so he could eat them, and particularly savored their fear. HE ALSO JUST LIKES KILLING PEOPLE. He's pretty certainly sexually assaulted people before, particularly in the context of intending to eat them.

pretty sure this is everything but the fact that i'm not 100% sure should speak volumes as to how messed up he is

edit: also as you can probably gather from all of this, he's pretty unstable when you get right down to it. not sure if that actually hits any of her pings but yeah