Never heard of a "Limerick". That's the problem with being a native - You aren't taught much of the language, but rather pick it up from other people, who(m) often butcher it. Being a foreigner, you are specifically taught the language, so you could likely correct the natives.
And I think, whom is a pronoun for the accusative case.
Kill them all!
...Whom?
That's 1 guy...
Giant ants, yay!