This... This is the side of Jaehan I was looking forward to seeing!!! Him coming out of his comfort zone. But, hey. It's a special occasion. It's Yoons birthday! 
SPOILER!!
Due to spoilers seen on social media. Jaehan and Yoon do not switch, Jaehan just takes control and Yoon loves it. tried to cover with the spoiler option but it stil might go through.

