As the manifestation of Hantengu's pleasure, Karaku showcased himself to be the most relaxed and laid-back of Hantengu's clones. The entire time he was battling against Genya, Tanjiro and Nezuko, he was constantly praising them and, instead of taking the battle seriously, he saw it as nothing more than a game, seeming to only take interest in the new experiences he was obtaining in the battle.
Yo ho ho, what do we have here? A small, frail demon slayer, huh? Well let's see what you can do!