Looking at the third panel... Yuugi? It's gotta be a stylized Yuugi, right? That gym uniform-esque top isn't standard issue demon attire, no matter how you look at it.

I think you're right. But it's hard enough to tell that I'm unsure if it should be tagged.

If you look at the bottom of the horn, you see the outline if a star. Yeah, that's Yuugi alright.

The rock is sweatdropping...hah

Even the rock is sweating... ^^;