Although Tonbokiri had already thought of the answer to this question, he does pause a moment to look like he's thinking about it. It's only fair to show Izuminokami that he's giving the question due consideration, even if it's a bit of pretense. And just look at how adorably eager the young sword is for praise-!

"Mm. Honestly, I feel your usual look suits you best. Although I don't understand all of how Aruji summons us, I think how we initially appear must be an image close to our hearts. I resemble my former master Tadakatsu in many ways." And proud he is of that.