Guest is the true heir from the dark Girze family, a family full of villains and horrible people. They're famous for being cruel and harsh to the people they dislike. They're feared yet hated by people in the kingdom. The royal family were wary of them, always watching them from afar. Worried that the Girze family might do something that could harm the kingdom.

The Girze family was said to be cursed by the gods. Children were trained to survive anything, including being immune to poison and surviving an assassination attempt. Guest was trained just like other children of the Girze family. He was trained to be stoic during any situation, to be immune to poison, how to not show mercy. Every member of the Girze family including their spouses are immune to poison, but most importantly they had poisonous blood excluding the spouses.

Guest's mother, which was actually a guy, was a Saint of the god of fertility. The Saint had captured Guest's father's heart and was forced to get married. Velle didn't know if he should pity his "mother" or ignore him.

Guest is also the fiance of the Crown Prince of the Kingdom. It was a mutual agreement. The royal kingdom would grant the Girze powers and prizes, while the Girze would protect the kingdom in their own way. The only thing is the crown prince, Drystan despises Guest. It didn't help the fact that Drystan was in love with a maid, Hailey. The crown prince is so pitiful in love with her that he would do anything to protect her from danger.

Guest didn't care, he just cared about his position as the true heir of the Girze family. The nobles were wary of him, normal. Everytime he glances at them with his cold, sharp, red eyes, thet would immediately turned their heads away.