The death of his parents forces a seven-year-old boy named Seo Hae Bom to move in with an adoptive family who have a young son of the same age named Jo Tae Seong. Seo Hae Bom is in awe of Jo Tae Seong – he considers the boy to be everything that he is not: tall, handsome, popular, caring, and worthy of love and attention. The diminutive Seo Hae Bom thinks himself inferior and is humbled by the kindness of the family that took him in.

Seo Hyun-Joo works as the leader of a webcomic planning team. She declares that she plans to remain single, but she receives confessions from two men: Hwang Ji-Woo and Park Do-Gyeom. Hwang Ji-Woo is the CEO of a pharmaceutical company. He has a cold personality and excellent business ability. Park Do-Gyeom is a popular webcomic writer. He is a sociable person. He and Seo Hyun-Joo grew up like siblings, but he has held a crush on Seo Hyun-Joo for a long time.

About a woman who lost her parents when she was young and who goes back to her childhood home and struggles to find out the truth about her parents' death.

After Aliens arrive, the story takes place in two time streams: 2017 and 2037. In twenty years, and by 2037, the world has been divided into a “Smart Earth” where artificial intelligence has created a utopian environment in which no diseases or crimes exist, and an “Ordinary Earth” where people still suffer from rampant plague and lawlessness.