Taeyeon is a conglomerate boy, he has his first love while in high school. The woman is Lee Soonkyu or better known as Sunny. However, Sunny leaves Taeyeon without a trace to make Taeyeon heartbroken.

And Taeyeon has a half-sister named Jung Soo Yeon or better known as Jessica, her father remarried with Jessica's mother. After the despair of his first love Taeyeon secretly liked Jessica and vice versa. They had a secret relationship without their families knowing. Because of the consequences his family will be a great embarrassment if this relationship revealed.

Conditions became more complicated when 
Tiffany come in Taeyeon's life story. Taeyeon's dad arrange married his son with Tiffany for business matter,  in order for their business to grow with the unity of their company. Taeyeon who did not want to disappoint his father accepted her father offer. Jessica who knows the news is very surprised and suddenly disappear from Taeyeon life.

Tiffany is a daughter of a well-known company in South Korea, known as Tiffany Hwang or Hwang Mi Young as her korean name, but she does not like the name because it sounds old. Tiffany gladly accept her parents request to marry up  Taeyeon, because she has loved Taeyeon for a long time. Tiffany is also Taeyeon's best friend when she was in high school. But for a long time they did not communicate.

The marriage was a journey and the family life of Taeyeon and Tiffany began. But instead of loving Tiffany, Taeyeon just ignores Tiffany by expecting Jessica back to his life. Tiffany always tried to make her the only one person in Taeyeon's heart. Can Tiffany be Taeyeon's only love? Will Taeyeon be sorry when Tiffany wants to give up because her love is never reciprocated? Is her love not enough for Taeyeon? Was her sacrifice not enough?