There's nothing wrong with loving villains, antiheroes and morally ambiguous characters! They can be interesting and compelling, even sympathetic. You just have to be mindful of why you like them and how you portray the things they've done in any content you create.

"I like this character because he's complex and I like exploring how someone can view themselves as the hero of their story while actually being a villain." Awesome!

"I fully acknowledge that this character has done bad things, but I think they have shown a potential to become a better person and I want to explore that without excusing their past actions." Great!

"I'm going to write an AU where I purposefully remove the aspects of this character that I find upsetting so I can just have fun with them. I will acknowledge this is not canon and acknowledge these issues." Cool!

"I know this character sucks as a person but I think their design/voice actor/etc is sexy and don't condone bad things they've done." Okay!

"I love this character who engages in horrible things that have real world counterparts that are still downplayed, like sexual violence and bigotry, and I am not going to acknowledge any of that. In fact, I might make excuses for these horrible things or, hell, I might actually like this character BECAUSE of those things." .....No. Stop it.

"Hey, want to see me take a morally flawed character and make them worse? So I can nut? Want to see that?" Shut up.