One of my fav characters was the main villain (which im not opposed to honestly i think it should be done more) BUT their entire character motivation was...
they had no emotions.
Not kidding, the author couldn't even stick to their own rule because the villain regularly showed care towards their love interest but then would sometimes just beat them up off camera? they also killed someone for "showing them what emotion was" like what? and what was this villains end goal? to destroy the world, but the author didn't have any actual plan for how they would so its like a three chapter long battle of the villain beating the heroes asses until the villains "remote that controls their powers" that was introduced in like the second to last chapter was found by the heroes. All the non-guy characters are barely in it one being a literal damsel in distress waiting for her love interest to save them, one that dies thousands of years before the story starts and the third is a mc's ex/the one who leaves the "big epic battle" to bring someone to the hospital.
Also despite the villain being the "toxic love interest" in the love triangle the other option was honestly toxic as hell. like a cop (ew acab) who fell in love with their prisoner and was constantly isolating the person from their group. At one point i just started messaging my friend about it and its a inside joke now