She's ex-mil

Arabella used to be of rank in the irken military, until a few things went south and she decided to get the fuck outta dodge. Because of her height she ended up in a captain's position- one she was very poorly suited for. A brilliant soldier won't always make a brilliant leader, after all. 

Arabella has a very gung-ho style of fighting now, but back in the day she wasn't a bad shot with the old plasma rifle. Most irken military equipment is standardized (I figure) so she could probably still pick up any empire-grade equipment and know how to disassemble it and put it back together again with her eyes closed. She doesn't really like using it though- plasma-charged weapons are messy and if they don't kill on the first shot then they put the target in a lot of pain. It's hooked up to her PAK here for guidance, basically allowing her to scope down it without adding a scope to the actual gun. 

Back then she didn't have her fancy lipstick or galaxy finish on her PAK. Or the hat. Frankly I think she looks weird without at least two of the three. And she used to tie back her antennae! Let 'em fly free, I say. 

This was done in a stream a while back! I'm still working on getting back into digital art, so bear with me.