Steven mentions that his sister Hayley was giving the coach a Rod Carew in the parking lot. Rod Carew was a Major League Baseball player for the Minnesota Twins and California Angels in the 1970s and 1980s. In addition to being the only major leaguer to ever be born in a train, he was one of the most prolific hitters of his generation. It should be noted that Steve is using R"od Carew" as rhyming slang for "screw".
Someone on twitter said this was the worst Treehouse of Horror episode ever. Given that the individual involved was a 22 year old, I put that down to internet hyperbole. So upon watching it myself I’m not sure where it belongs.