After his parents passed away, the government and the country faced the world alone and moved forward alone.And in this cold reality, the only person who is willing to light a lamp for him and give him warm care is his childhood sweetheart and classmate - Ye Bai ツミ.However, Musmi hides an amazing secret - she is the daughter of the spy family "Ye Ying Family"!What's even more difficult is that her biological brother Kyichiro had an almost paranoid desire to protect her, and even regarded Taiyang as a threat, intending to get rid of it quickly. In order to stop this murderous intent, Taiyang and Musmi decided to take the most unexpected step - to get a fake marriage!Because there is an iron rule at Ye Ying's family: family members should not kill each other.A battle of wits with marriage as the shield began, and the fates of the two young people were closely intertwined...