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 as he 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.
Things become slightly different for the duo, however, after Seo Hae Bom and Jo Tae Seong end up in the same high school class. All of a sudden, they are spending more time than ever together at home and at school. Although they have developed a sort of brotherly love, now united in the same class, an unexpected romantic spark ignites between the two – but what will Cupid have to say about all this?