It all started out as a teacher and student relationship, feelings unsaid until thunder and lightning shook the boundaries and put them to the test. Four weeks later at Minseok and Jongdae's wedding was where their future was dealt out like a pack of cards. Two blue lines held what lied ahead of Do Kyungsoo and Kim Jongin, two blue lines that sealed them together and broke science. Do Kyungsoo was pregnant and with Kim Jongin's, his English teacher's, baby. Nine months later and the baby was born. A beautiful baby boy, a splitting image of Jongin with Kyungsoo's lips, called Kim Taejoon. Sleepless nights ensued but smiles were always painted on Jongin and Kyungsoo's lips as they watched their baby boy grow. Fights happened, of course they did yet they always managed to overcome them. It was when Taejoon was eight months where the thing that ultimately tested them arose. That tested their relationship, tested their love but a few weeks later and everything was back to normal. When Taejoon was eleven months old, Kyungsoo and Jongin were married. The Kim family, a family full of love and closeness but has their moments of distance. It is something Jongin and Kyungsoo take a lot of pride in. They did this, they created this and they will keep it like this. But children are made to test. So it is a good thing they only have one, right? Wrong, sometimes they wish they did.