This should be a Female Pryo taunt...like, you are a Female Pyro, run up to someone who's waiting for a high-five and press 'g', lean back as though you're about to high-five them, but then instead spin 180 degrees and sit on the other person while giggling (and maybe if the player you're sitting on is a Scout, he'd say "Freakin' unbelievable!"). Then the get up after a second or two, along with the other player, and go back to fighting. It would be as rare as the Spy's "Spycrab" taunt, but about a million times cuter.
How. may I ask did you pose the googly gazer? (If that is what that is)
Interesting technique in submerging the scout somewhat into the floor to give him that crushed look
A tip I would like to give you that I'm seeing in alot of the 'HDpyrobutt' model posters; do check the ankles, I've worked with the model and I know its hard to avoid, but make sure your ankles dont bulge, you might be able to quell that by using the XY position tool and nudging it backward some, or perhaps forward even.
May I also inquire you on how you achieved that matte texture look? Did you modify the VMT's or a rendering effect within the software?