Shan Yi Fan suffers from a strange disease; if he has five seconds of physical contact with someone he will change into that person's appearance and won't be able to change back until three days later. One day, he transforms into Luo Luo's cheating ex-boyfriend during the middle of their arguing and she mistakenly follows him instead, only to accidentally kiss. Surprisingly he transforms back to himself! With Luo Luo's kiss being his antidote, what else is a domineering CEO to do but to keep her by his side at all costs.

Orphan Ah Young is a financially struggling 23-year-old who takes care of her 8-year-old sister Dan Bi while juggling part-time jobs. One day a 28-year-old man Yoo Sang appears in front of Ah Young offering to be her dad through a signed agreement.

After being pulled into the webtoon world created by her father, a surgical resident gets entangled in a murder mystery involving the story's hero.