Arashi nearly choked in his drink, but being a ninja he managed not to spit anything out.

He had the inexplicable urge to show off his skills, it might have been that his house was full of crazy mercenaries from Wade's world of crazy and weird and he didn't want them to think he was powerless.

Just might have been that reason that he used his flash moves to go into the living room, for some of his knives.

Maybe.