"My love for you is like diahorrea; I simply can't hold it in" is all Kyungsoo remembers before he passes out in shock when he realizes he is discovered for breaking into someone's house to use their toilet in the hurry of his upset stomach. 

An anonymous player keeps sending Sunggyu many hearts on the most-played online game "Cotton Crush" and being the dense being he is, he gladly accepts thinking there is no hidden motive. But what if one day, a real human heart was given?