Whopper rhymes with:
bopper, chopper, clopper, copper, cropper, dropper, gropper, hopper, improper, kopper, opper, popper, proper, propper, shopper, stopper, topor, topper
Whopper sounds like:
wafer, waifer, waiver, waver, wavra, weaver, webber, weber, webre, weeber, wever, whobrey, whoever, wieber, wiper, woofer