I know, it was a joke cause of his bunny fetish. Kyuu doesn't suit him at all, she's too much of a thug. If there is a love rival to Haru it would be LouisI've finished the series. Kyuu doesn't really mean anything to Legoshi. Haru is The Woman for him even in the end.
True though that the romance angle of the series is down played in the final arc.