Sitting on the bed had gotten boring after a while, so Yong Soo had opted to lie on the floor instead -- it was all squishy and carpeted and nice! - with a book spread out in front of him. So it was like this that he had looked up to a knocking on his door and called out, cheerfully, "Come in!"
And it was like this that he'd grinned at Matt as he peeked in, and then looked at Matt weirdly when the Canadian had referred to himself in third person (Yong Soo did that to Matt sometimes, but never Matt to Matt!), and afterwards told him that Matt didn't need to treat him to snacks again since he already did it so many times--
-- but then it had really gotten too odd, so Yong Soo sprung over to the blonde and, upon closer inspection (because nothing escaped his Korean powers of deduction!) and with a widening grin, realised,
"HEY, you're not Matt, da ze!"