I think that was perfectly worded to corner Ralph.
I think the BJ happened, and I think Ralph definitely didn't think it was rape. Legally it absolutely would be, however in my own morals, I'm not sure. I think women get drunk as a way to act out, including sexually. Guys also will coerce women into getting too drunk. I'm not sure a woman willfully taking drugs (they are aware of what they are taking, no roofies) and then actively participating (meaning she isn't fully passed out) in a sexual act should be considered rape. It's trashy on both ends, and while the guy gets the blame for having "ulterior" motives, I don't believe women are innocent on that intention either.
Ralph doesn't deny the blowjob, only that there was rape. I don't know if that's under legal advice or out of pride. Alice is definitely the most attractive woman he's been with, and I think he is/was proud of scoring with her, and not embarrassed about it or even aware it would be perceived as being a trashy morally gray event.
Alice stole from him the best he'll ever do, which is getting fucked up with Baked's sloppy seconds and making it to third base with damaged goods.