[The running her mouth isn't particularly impressing Shun, but at least she's asking about rules upfront, unlike other people who often end up complaining about him doing something they consider below the belt halfway through the spar. With that in consideration, he'll at least respond to the question.]

My only limit is no lasting injuries, since it's a spar. There's not much point fighting against someone if there's no risk at all to it.

[Even if that risk might just be a bruised jaw or a bloody nose. Regardless, considering she's being so hasty about it, Shun holds his naginata ready, since he wouldn't put it past her to just charge him as soon as the rules are established.]