"Servants"

Ciel Phantomhive, from Black Butler, is a complex character defined by his cunning, precocious maturity, and cold determination after suffering severe trauma. As a young and adult earl and the Queen's Watchdog, he is meticulous, competitive, arrogant, and often ruthless in achieving his goals of revenge. Despite his coldness, he maintains a hidden moral conscience.
Here are the key aspects of Ciel Phantomhive's personality:
Cunning and Manipulative: Ciel is extremely intelligent, capable of maneuvering complex situations to his advantage. He is a natural strategist, often compared to a chess master.
Cold and Ruthless: Due to his past trauma, he has become a person who does not hesitate to eliminate obstacles, showing malevolence when necessary.
Serious and Responsible: He acts with extreme maturity, taking on the burden of the family business (Funtom) and doing the dirty work for the queen.
Proud and Competitive: He has great confidence in his abilities, which sometimes borders on arrogance, and he deeply dislikes losing or tying.
Traumatized: Suffers from post-traumatic stress disorder, reliving the painful past, which sometimes makes him vulnerable or fearful in extreme situations.
Loyal (in his own way): Despite his detachment, he shows loyalty to the queen and, at specific times, affection towards close people like Elizabeth Midford.
Hidden infantilism: Sebastian has pointed out that, despite his maturity, Ciel still retains childish and arrogant traits that need to be corrected.
In summary, Ciel's personality is a mixture of a child who was forced to grow up too fast and a ruthless leader driven by revenge.

Riddle Rosehearts, from Twisted Wonderland, is the strict leader of Heartslabyul, defined by his manic obsession with the Queen of Hearts' rules. He is studious, disciplined, short-tempered, and authoritarian, imposing severe punishments for any transgression. Although he appears cruel, he is a perfectionist conditioned by a repressive upbringing who seeks to learn to be more flexible.
Rigidity and Rules: It is governed by strict compliance with the rules, considering them fundamental, no matter how absurd they may be.
Fierce Temperament: Gets angry very easily (hot-tempered) when someone breaks the rules or questions their authority.
Authoritarian and Hardworking: He is an outstanding student who feels superior, demanding obedience not only in his dormitory but also outside of it.
Internal Contradiction: Despite his severity, deep down he is kind and wants to form real connections, relieving the pressure of his restrictive upbringing.
Evolution: Throughout history, he learns to soften his attitude, becoming more forgiving towards himself and others, although he remains firm.
Genuine concern: Although strict, he makes sure that no one in his dorm fails or is expelled, sacrificing his time to help them.
In short, Riddle is the personification of contradiction: a leader with a "heart of gold" hidden behind a shell of severe rules and a volatile temper.