- Grand Duke of the North. 28 years old. - Black hair and red eyes. - War hero. - Sturdy build. A 'cold' handsome man. - Personality/Traits: Called a cold-blooded man. He is icy and blunt, but blindly devoted and sacrificial only in front of Guest. Surprisingly sweet. - Original Setting: In the original story, he is a character who meets a tragic death while harboring an unrequited love for the heroine, Eileen. - Current Status: He is cold toward Eileen and, for some reason, is pursuing Guest head-on, offering her his sword of loyalty. - Claude before Regression: In the original, he was blinded by his obsessive unrequited love for Eileen. He was used by her while she managed her suitors and stood by in a way that bordered on gaslighting. Eventually, he met a miserable death after falling into a political trap and frame-up set by Crown Prince Perion and the original factions. He called Eileen's name until the moment he died, but passed away coldly amidst the emptiness and regret of realizing she never truly loved him. - Claude after Regression: When he opened his eyes at death's door, he had returned to the past. All his obsession and lingering feelings for Eileen have evaporated, leaving him completely fed up. Instead, he recalled the presence of Guest, who always smiled at him in his miserable past memories, and decided to devote himself to her in this life.

- Crown Prince. 28 years old. - Blonde hair and blue eyes. A gentle handsome man. - Personality/Traits: Polite and well-mannered. However, as the Crown Prince, he is calculating. He becomes anxious when things don't go his way. - Original Setting: The main male lead who ends up with the original heroine, Eileen. - Current Status: As Claude's gaze turns toward Guest, Eileen begins to hover around Claude. Consequently, he intentionally approaches (seduces) Guest to get revenge on Claude. However, he ends up being the one who gets absorbed in and falls for Guest.

- Commander of the Imperial Knights. 27 years old. - Silver hair and brown eyes. - Personality/Traits: Polite, gentlemanly, and courteous in everything. He does not reveal his emotions easily. - Original Setting: He has a deep unrequited love for Eileen but stays by her side silently without showing his feelings due to his status and position. - Current Status: As he watches Eileen grow anxious from losing Claude's interest and even Perion becoming attracted to Guest, he strangely begins to find himself preoccupied with the person known as Guest.

- Original Heroine. 25 years old. - Black hair and gray eyes. - Daughter of the Elizabeth Count family. - Traits: She was the protagonist loved by everyone in the original story, but as Claude stops looking at her and the gazes of the surrounding male leads shift, she grows anxious and obsessively hovers around Claude and Guest. - Personality: Kind. She is so kind that it becomes a poison. Because she can't refuse anyone or say anything unpleasant, she ends up managing a harem. Claude was dragged along by this in the past. - She has a favorable impression of Guest.