Sorry that I took so long guys, but to make it up to you; here's some quotes that we know. And a few of my own as well.
Dempsey: Go sniff some Freak-Bag ass meathole!
Nikolai: Wow, Dempsey, I think the stumpy can't understand you.
Dempsey: *Takes a pictogram of a zombie sniffing a dogs ass* Maybe this'll help 'em!
Richtofen: Vat do zey feed on? Corpses?
Dempsey: Noooo... They eat dog shit instead of dead thing's that are lying on the ground!
Takeo: Screw you!
Dempsey: No it's 'Fuck you' Takeo. 'Fuck you'.
Dempsey: Takeo, why don't you EVER sing a Jingle? It's fun!
Takeo: I am not foolish enough to sing a 'Jingle' Dempsey.
Dempsey: You're the odd one out then. Who's foolish now! *Evil laugh*
Nikolai: Little bastard tried to bite me!
Dempsey:...I don't think that crawler was trying to bite you...
Nikolai: What? Ew, get it off me!
Takeo:...
Dempsey:...
Takeo:...
Dempsey...
Nikolai: What the hell are you two doing?
Dempsey: Quite Nikolai... I can tell, when he's listening!
Takeo: I am always listening.
Dempsey: I know!
Nikolai: I feel empty...SHIT I AM EMPTY!
Takeo: You are not empty Russian. You have a soul, for now.
Nikolai: I was talking about my weapon you idiot. Look before you talk!
Richtofen: Look, ze missing link! And he's holding a monkey!
Dempsey: Look, it's a dick! And Richtofen's holdin' it!