It's not Wataru? Heck, I'm okay with Himegami, we've been waiting since the first few chapters KNOWING he's involved in the story. Just like Hayate's brother - they mention him once and with every chapter we look forward to his certain plot-related appearance.
Although the first season of the anime DID f*ck it up. I mean really? This character that sound like the vital part of the whole manga's climax turns out to be a lame puns-spouting moron in a mask? Oh well, I bet he's taken a level in badass since then. Of course nobody beats Isumi, but still, I look forward to his probable appearance.
So "28th" means "28th butler of Sanzenin family"?