prof | Natsuhi's Riddle: Grey

Hahahaha. It's the sort of puzzle that brings out one's upbringing. Perhaps it was a bit too hard for you.

What did you saaaay?!

A keybaord? Like on a piano?

That's right. The blacks and whites are the pattern of colors on a keyboard. In which case, you must already known the right answer.

Ready? It's Krauss's turn now. We'll solve it in a flash and teach him a lesson, okay?