Gay bait. Other parts were full of shit araki forgot or abandoned as ideas. Kyo isn't important at all and already played her role, she shows up regularly although not that involved in the plot, she will have a role to play with holy in the end. Karera is something Araki abandoned and for the better. She litreally had no reason to be in the story and also he fucked up with her because 1. She's a part of the time when Josuke's goal was finding out his past. Something he found out and now has shifting his goals. 2. Her involvement is not clear since there's a photo of her kira and josefumi shown but kira doesn't even know her until he and josefumi fight damo and she's just stalking josefumi. Also not having the villain revealed 80 chapters in is nothing out of the ordinary, part 4 and 5 did similar things but they hinted at who the villain is without showing him, this time Araki's doing it right keeping us in the dark until the grand reveal. Rock niggers are punchable and perfect antagonists.