Seung-su, who had lost her lover to Dong-Ho and lost her heart, is comforted by her body and mind to the associate woman who happened to meet her. She does not care about her mature kindness or marital sex, regardless of her age or relatives. But what is this? I found out that the aftershock was a new mother of my old friend Dong Ho! My ex-girlfriend who loved hotly. My closest friend. And a friend who has become the most loved in the world. The secret relationship of four people begins.