She and he are best friends. She loves him, but he loves her friend, while his twin brother likes her. One day, they ended up having a secret relationship: he asked to be friends with benefits with her. She agreed because she loved him. In the end, he got engaged to her friend, and they went to study abroad together. He asked her to end their friends-with-benefits arrangement and asked her to go back to being his best friend like before. What will she do about this relationship now that she's pregnant with his child, and his twin brother is stepping into her life?