Whomsoever rhymes with:
whatsoever, whosoever, whatsoever, whosoever, bever, clever, devore, endeavor, endeavour, ever, forever, grever, haver, however, kever, klever, kochevar, lever, mcever, morever, never, sever, trevor, whatever, whatsoever, whenever, wherever, whichever, whoever, whomever, whosoever