Ahaha, thank you for pointing that out! You're right, looking back on it, he does have a tendency to slip into overuse of that particular quirk — I think it's partially because I'm working to make my characters' voices distinct that it's been happening. Yagyuu puts a lot of emphasis on the idea of being "a gentleman" and having a sort of overly polite and courteous affect, so I try to give him a kind of lofty and pretentious way of speaking as a result, which leads to a lot of "Mm, I suppose you could say that", etc, etc.

But I'll keep an eye on it in the future and try to find ways of toning it down or choosing different phrases every so often to get the same effect! And thanks again for letting me know, because I hadn't even noticed that myself.