[bykovich2]

Not exactly: Mayella Ewell and Tom Robinson did not, in fact, have sex. Tom rebuffed Mayella's advances, and Bob Ewell concocted a rape as retribution for Mayella's attraction to a black man. However, the book strongly implies that, at some earlier point, Bob Ewell himself had actually raped Mayella -- perhaps habitually. It's not lingered upon, but the implication, while brief, is difficult to oppose.