he probably remember whatever he saw on the uke's phone last time.... i wonder if it was the picture of the crossdressed uke that the red haired guy use to blackmail the uke. the first time he also got hard after seeing whatever was send on the uke's phone and even jerk off on top of the sleeping uke and now this...
i'm not sure what he saw but its probably the uke dressing up as a girl and thats what got him hard.. the red haired did say he was looking at some pics he found in the old files...and sangwook did say ''i do like him, but not in that way'' so he got hard cuz the uke looked like a girl??? and everytime he remembers it he gets hard
Not him getting hard from cuddling