He doesn't like Levi. Hamel doesn't get along with most people, but Levi is extra annoying because of his disregarding attitude. Hamel hates being ignored and can't stand it when people brush off what he has to say, so it makes him act even more obnoxious just to get a reaction.

…and since Hamel is prone to ridiculous leaps of logic he's convinced that Levi's cleaning obsession stems from some deep FEAR OF GIRLS because the way he behaved at the underwear tree.

Violin magic will probably happen again, Hamel loves to abuse his powers.