I was watching undertale comic dubs when I saw this video.....

I haven't played undertale (though I'm planning too.) But I've watched markiplier and Nicob play it. Not all of it. Just up when sans and papyrus appear.

and I've watched all the endings....

But back to the question.

Is sans human?

It would explain a few things. Like how he was bleeding when you defeat him in the genocide run..... and why his sprite is always smiling...

But there are a few things that bothers me. If he's human... how does his eyes glow? How is papyrus a skeleton and he isn't? If they're not biological siblings how did they meet? How did he get to the underground?

So... what do you guys think?