Well known cases like Darren Sharper, used drugs like XANAX and AMBIEN, which he would crush into a powder and serve in a drink.
Alcohol lowers inhibitions already but when used with those drugs, it will slur your speech, slow down your movements, and erase your memory, or badly blur it. The real scheme is that a lot of the women just thought they got black out drunk.
Puff, probably GHB in drinks, MDMA crushed and put into drinks (this was popular for awhile in clubs scenes). that plus alcohol. it's not going to FORCE you to have sex but it may make you more open to having it, and it will 100% impair you from saying no.