HAHAHAAA!! I'm sorry but that is soooo funny!! The pets were making their own holidy LOVE Mommy Day, it sounds like Maxwell took it too seriously tho. lol Koby did the "humping" thing too when he was around 8 months. I freaked out and within 2 days I had him neutered. I got him when he was 7 months so I KNOW it was a dominance thing. The only thing I would suggest is make him stop as soon as you see him doing this, then a command like sit or down to prove you are the one in control. I'm not a trainer or dog professional by any means so I could be wrong but it's just a suggestion. Anyway once Koby got "snipped" (I really hate that word) he didn't do the humping thing anymore. Good luck, he still a puppy so he'll get over his literal affection for you. lol
Andi