Can a neutered male cat hump??

[Don Juan's mom]

Yes. Don Juan (who was neutered at 18 months) occasionally mounts Zerlina, to her everlasting annoyance. (Yes, she's spayed.)

[Medusa]

My Boo is nearing 19 years old and I had him neutered when he was around 6 months old. He mounts my nearly 20 year old cat Pigeon every day. He bites her neck really hard, too, to the point where I have to rush over and make him get off her because he makes her cry. Honestly, I'd have a house full of kittens if he hadn't been neutered.

[smokey the elder]

It can be a dominance thing. When I adopted Spike (young neutered male) Pink Nose (older neutered male) did that to him. It's kind of strange, but not uncommon.

[Pinot's Mom]

Our RB cat CK was a Tomcat from the street. We had him fixed when we took him in (and THAT was an experience in itself!). He never knew his plumbing didn't work any more and tried until the day he died; he had mating scars all the time.

[GILL]

We have had them neutered from 6 months to 8 years. They all will still go at it when they get the urge.