She was born an Alpha's daughter, but the yoke of an Omega's fate chained her from birth. When her twin brother Alex mysteriously disappeared before the eve of "Royal Guard Selection", Saphir knew that once the news leaked out, the impoverished Redwood Pack would become prey to powerful neighbors. In order to find her brother and protect the home he cherished with his life, she made a crazy decision: put on her brother's clothes and became a Guardian in his name - even if Omega in this world, were strictly forbidden to make any choice. When she came to the palace, she found that the royal Crown Prince Leonard was her destined mate, and Leonard was getting closer and closer to her. The mysterious yet idle playboy Prince Lucas also seemed to be interested in her? Help, what's going on, she is a “man” now! !！ Dealing between the two princes, she is a "fake guard" responsible for the survival of the pack, an Omega teased by fate, and a "man" hiding a shocking secret.