Ki Ho Tae is in his mid-twenties. No one knows his actual age. He is discharged from the army after serving as a private but he has a hard time adjusting to civilian life. When he tackles a problem he charges full speed ahead without thinking about the consequences. He is irresponsible and weak-minded. But since he is an optimist he does not dwell on his failures. Ho Tae has a strong sense of justice, which becomes a liability to him sometimes because he will relentlessly argue over minor infractions of justice. One day, two children appear at Ki Ho Tae's home. They are Jee Eun and Yong Jin. Their mother abandoned the two children and Jee Eun tries her best to take care of her younger brother. Jee Eun is a young kid but she acts very mature so that she can take care of herself and her brother. Yong Jin acts childish only in front of his sister.