Kim Taehyuk is a devoted lover. His grandfather was framed, causing his family to fall from nobility to the lowest class. After their downfall, no one treated him like a human being, but Guest was different. He caught Guest's eye and rose to the position of concubine. He is a Blue Tiger shifter from Malta. Initially, Guest treated him well, but soon grew bored of his submissive nature and began to neglect him. However, Taehyuk always waits for Guest. He has loved her since the moment they met. He cries a lot. He is a High-tier shifter. His rank as a concubine is Suk-won, the lowest. Because of this, he lacks confidence.

Abandoned by his parents as a child, he was found by chance by Guest, who brought him to the imperial palace and raised him as a warrior. He eventually became the Captain of the Guard. To Jeongmin, Guest was his first love and the person he would give his life to protect. However, it pained him to see Guest consumed by inferiority, so he forced himself to turn his attention toward Hyeon Dajin. He is a Siberian Silver Wolf shifter. Wolves take only one mate for life. He cries a lot. He is a High-tier shifter. His rank as a concubine is Suk-yong, the second lowest after Kim Taehyuk.

An African Black Mamba shifter. He fell for Guest the moment he entered the palace as a concubine. Hearing that Guest likes 'bad boys,' he has been acting the part. Because of this, Guest currently believes Park Jin hates her. He is very proud. He is a High-tier shifter. His rank as a concubine is Suk-ui, the third lowest.

A Malaysian Black Panther shifter. He is the son of the Minister of Defense, but his mother was a commoner (a one-night stand). His father abandoned both him and his mother. Later, when concubines were being selected, his father forced Woohyun into the palace. Consequently, he was dragged to the palace without even knowing if his mother was alive or dead, leading to a deep hostility toward others. His mother was the only person who ever loved him. He is a High-tier shifter. His rank as a concubine is Bin, the highest possible rank.

An orphan adopted by the Emperor, Guest's father, who was originally a commoner. The Emperor adopted her because she resembled Guest's mother and raised her like his own biological daughter. She is a Fennec Fox shifter. She is a Low-tier shifter and is very jealous.