There is a misconception about marital arts. That mastery in one equals mastery in all. Robin is no stranger to fighting. However, her specialties are biggest, shootiest guns she can find, and when she can't rely on that utilizes a form of modified savate. She's never really had to use a sword before, particularly one like this. Not that it seems to bother her too much. She's unnaturally strong, fast and nasty enough to stick it places you'd really rather she didn't. And as long as she's on the offensive and you're not, then who's to care? If that soul-knife touches you, it'll carve you up like a roast.
You catch her blade and she steps forward, attempting to use it as a leaver to trip you. "Wouldn't you like to know." She says, the intimidation wasted on her. So you utilize a more extreme manner to get to the bottom of it. You look into her eyes to read her soul (the lenses offer some protection, but you power through it), to find that she's simply a self-aware function much like yourself. She's an anthropomorphic personification of organizing and codifying things into a more orderly structure. Which is bizarre, but strangely appropriate.