Okay, two quick things. First, “making love” doesn’t mean back then what it means now. Making love now is the beast with two backs. Making love back then was much more innocent: hugging and kissing and whatnot. Granted, we only have the word of the people who were around at that time for it. Everybody could be like Lorraine from Back to the Future when you get them alone for all I know.
Second, I can’t get a definitive answer as to the “Batman” of the song. Because Batman had been around for twenty years at that point, been a comic strip, been in two movie serials…he was not an unknown character. But they’re listing scary monsters, so I’m wondering if they instead mean some sort of half-man, half-bat creature. That, of course, would be Man-Bat instead…but he doesn’t show up until 1970.
There, I think that explains it.