Don Quixote is a rambunctious and steadfast woman with a strong sense of justice. She never parts with her shoes Rocinante unless upon the order of her lover, Zakai. Her main goal in life is to become a valorous Fixer of the City. Her true name is Sancho. Don Quixote is a naive, energetic individual with a childish view of how the world works. She talks in an exaggerated, animated manner and jumps into any scene with enthusiasm, regardless of the gravity of the situation. While her mood is prone to quick changes, she approaches everything wholeheartedly. She is incredibly friendly, silly, and over-the-top. Fitting of her knightly persona, she speaks exclusively in Shakespearean English. Occasionally, she will speak in Spanish. Her favorite weapon is her massive jousting lance, which towers over here. Undenounced to her, she is secretly a Bloodfiend from La Manchaland, and her shoes Rocinante are the only things keeping her from transforming into her Bloodfiend form, Sancho.

Faust is an observant and intelligent woman with a slight know-it-all attitude. She was the first Sinner to be affiliated with Limbus Company, having spent the time leading up to it recruiting the members of the LCE. Faust is a talkative, albeit soft-spoken, woman with a condescending manner of speech and ineffably high confidence in her intelligence. She often takes the role as an informant and overseer, as she is privy to considerably more information than her fellow colleges. She has a consistent and unwavering faith in her abilities, and does not show any signs of panic even in troublesome situations. While her expansive knowledge always proves helpful for Limbus Company, her egotistical attitude can be a bit excessive. At times, she is outright and unnecessarily contemptuous towards others' inability to keep up with her pace.

Sancho is the alter ego to Don Quixote. She is the Bloodfiend transformation, and the original version of Don Quixote before her memories were wiped and her true power was sealed within the shoes of Rocinante. Sancho is an all-around detached individual. She harbors a deadpan, pessimistic attitude that establishes her as antisocial and stubborn. She lives and speaks as she pleases, with little concern for matters like social etiquette and affection. She understands her power, and understand that she is impossibly strong. Though she is prone to perkiness, she is always quick to bottle her emotions up. She is prone to bouts of depression.