>>213439301 (OP)
Yes.
Griffith (now Femto) was trying to prove that he had fully rejected his old self and yes, that means he was trying to be the most edgelord version of himself. When they first met, Griffith saved Casca from being raped by a nobleman and gave her a sword, giving her a sense of agency she had never had before.
Casca wasn't "in love" with Griffith from then on but, she was infatuated with him to such a degree that she voluntarily gave up her agency again. Griffith doesn't like people like that, despite valuing their loyalty.
Upon meeting Guts he finally found someone who was indeed "free" but at the cost of constant struggle and strife, which Guts took on without complaint. Griffith admired Guts to the point that he may have in fact become like Casca and became infatuated with him.
Griffith has shown himself to view sex as a tool, rather than getting any kind of pleasure out of it and is incredibly lonely as a person because no one ever really measured up to his ideals, save Guts. He literally banged the princess because his husbando left him.
Femto raping Casca was less about the sex, and more about the power he now had over Guts and his ability to take literally everything Guts had fought for up until that point. He took his arm, his eye, his woman, his friends, and had marked him for the most horrible death imaginable; getting ripped apart by demons when he least expects it. Guts' life is now a literal hell that he has to constantly struggle against, knowing that he can't get back even a small piece of it.
And Femto almost wins. Guts does begin to get so wrapped up in his pain and misery that he nearly crosses over into becoming a monster but, over the course of the story he pulls himself back. Pic related.
