Eunsoo runs a flower shop with his mother. But one day his single mother told him that she had a boyfriend with marriage plans in mind. Furthermore, his mother's boyfriend has twin sons. Unexpectedly, the twins who were his soon to be little brothers, upon their first meeting treated Eunsoo with utmost kindness and try to make forbidden physical contact with Eunsoo. Summary of MMS: Mom suddenly wants to remarry, but the man she's dating… he has twin sons? Do the brothers know about my confused feelings when they tell me they like me? Since we’ll be a family soon, we should try to get along, but… This is way past being close. Don't you think we're being too open with each other?