Well, he helped Umi kill Touga, but that doesn't quite count I don't think because a) Umi did most of the 'work', with Nall just helping, b) it's not like it particularly inconvenienced Touga for any length of time.

>Insert shit joke attempting to lighten the mood here.

"Touga, you should really try to make something of your new life. Next time, try to get the opponent to jam their sword on your ribs, so you're an inconvenience for at least 10 seconds."

"This is probably a stupid question, but . . ."