your yearly reminder that Baby It’s Cold Outside is a song about a woman having CONSENSUAL sex, at a time when premarital sex was frowned upon. The female singer is offering up the token demurrals society expects her to, because it’s expected, not bc she doesn’t fully intend to stay and have awesome sex with a dude she’s into. The male singer knows this, and is in turn offering her an excuse to give to the neighbors in the morning (“it was too cold for me to go home, the only responsible thing to do was spend the night at his place. because of the weather, get your minds out of the gutter”). A 1950s audience would have understood all this, but the nuance gets lost in a modern age where women are actually allowed to say yes when they mean it.
Also the “hey what’s in this drink” thing was a common joke at the time, where the punchline was that there was in fact nothing in the drink. the woman’s making a joke that she wouldn’t do this if she was sober, oh goodness no! it’s only a joke bc both she and the man are in on the punchline: she is sober, and is only staying bc she wants to