He has quite complicated feelings towards her imo. But no he doesnt hate her that much since his affection score is not that low. He s just a dumbass who didnt realize how he was starting to like penelope even before the brainwashing and i think that is partly because he doesnt see penelope as a sister and cant admit that to himself. So he acts like he hates her instead? Also could be just cuz he s a bastard but who knows.
He never hated Penelope, but he also never believed in her at all even before Yvonne showed up.
Yvonne just preyed on the guilt he was feeling which made him bring her to the party.
I'll give you a little spoiler but it was hinted that he actually sees Penelope not as a sister but as a woman.
I think it's not so much that Derrick hates her but the fact that he hates not being able to own her like he desires, since Penny has to play the part of the little sister.
Dude is romantically obsessed owith her (my guess after seeing the caged bird).
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he was brainwashed by the witch so does that mean he doesnt hate penelope that much? or am i missing something?