Someone who is just a horny dude. An "H Dude" is someone who is always dtf and have a good time.
You can replace that person's name with the term H-Dude. Forexample, if his name is mitch, you could say.
"Mitch, stop being such an H dude."
"H dude, stop being so H all the time"
"Stop being such an H dude."
"Mitch....NO. Stop it H."
When someone is getting loot a group of guys may cheer, the letter H really loud.