The undeniable seduction of first love.　　Ahn Dami is home alone in a house where her husband doesn't come back. He doesn't come back until morning and she's alone again. She goes to the fitness club to work out. However, her target is not …

503号的秘密从母亲继承汽车旅馆的京淑。每到周五下午两点，她们两人肯定会像竞争一样，只寻找503号。中年男子“秀敏”和另一个男子“排管工”就是该主人公。对散发着厚重气息的“秀民”感兴趣的京淑真想知道他为什么在同一时间一个人只找一个房间。她没能控制住好奇心，终于在503号上安装了监视器…