Someone once described Xenia as "dense as ice, as hard as iron, and as elastic as rubber." Perhaps they weren't being poetic.
She is 5 times as fast, plus 250 times as strong, as a worldclass athlete of her size, gender, and build.
Yes, she can bounce, and so can her fists. Fortunately, she tries to avoid confrontations. Unfortunately, that's not always possible when you're homeless and afraid.