After BaekYeon dating news comes to the spotlight, there was another couple of SM was dating secretly until there were news coming out. 

Hyoyeon and Yunho dated  secretly for a  month. When they both know what Baekhyun and Taeyeon are going through, they started to see each other less because scaring what will happen to them.  They was hoping that no one will notice their relationship. Until 1 day, a scandal came out.