'Bastard' is the word you're looking for. [He's eying her levelly, voice still low, trying to assess just how honest that threat is. They'd started this encounter with her pointing a weapon at him, after all.] 'Ass' is another one I get a lot. 'Goat' seems more your style, though.

So, why aren't you leaving me behind right now? I'm a liability. No weapons, slow, new. I know you don't like me. You don't even know if I'm useful. You make a habit out of helping anyone you run across?