Catherine Foundling (formerly the Squire) is apprentice to the Black Knight and the protagonist and narrator of A Practical Guide to Evil.
Background
The exact place and time of Catherine's birth are currently unknown but she was raised in Laure, former capital of the Kingdom of Callow. She was a ward of the Laure House for Tragically Orphaned Girls until the age of sixteen, where she was taken under the Black Knight's wing as a claimant for the Name of Squire. The color of her skin indicates she is at least a half-blood Deoraithe, though she was raised as an ethnic Callowan and does not know the Old Tongue.
Personality
Catherine is generally brash and aggressive, although she usually manages to be unpredictable without being reckless. She has a sarcastic streak that tends to come out when she is under stress, even if she doesn't want it to.
Her underlings have noted that she has an expression she adopts when she is at her most dangerous, which in commander Juniper's words "looks really creepy on a human".
Relationships
Catherine is liked and trusted by her immediate subordinates, Nauk, Robber, Juniper, Aisha, Hakram and Ratface. She in turn trusts in their skills and loyalty to help pull her through whatever challenges she and the Fifteenth Legion encounter. She has a romantic relationship with the legion mage Kilian.
She considers Amadeus to be both a mentor and something of a confidante. She does not trust him with all of her secrets especially regarding her ultimate objectives but she does place great value in his advice.
Prior to his death, she had a hostile relationship with William. While she was willing to use him to achieve her own ends, she considered him extremely frustrating to deal with and resented the way that he seemed to always get everything he wanted without effort. She had a nemesis story with him, but it was resolved with neither meaningfully dead and she killed him later.
Besides the Lone Swordsman, she is also nemeses with Akua. She dislikes Akua even more than William, as her schemes tend to be destructive an irresponsible as well as difficult for her to deal with, and she knows that unlike the Lone Swordsman, Heiress doesn't have good intentions behind her actions.
Appearance
Catherine has several times been noted to be short, though by Book II she is of a height with Amadeus - though he himself is noted to be a short man. She is dark-skinned, like most people of the Deoraithe ethnicity, and also of the slight build most common among that people. She's been shot with crossbows at least twice in ways that left small marks even after healing and has a long reddish scar across her abdomen inflicted by the Lone Swordsman. The wound healed by blood magic, but the scar has yet to recede.
Name History
Catherine was originally offered the chance at the Name of Squire by Amadeus. Due to his assistance and her own actions, she was able to defeat the other claimants and take the Name fully for herself.
During the Battle of Marchford she asked Masego to try to unlock her third Aspect early, but the attempt led to it being corrupted and forcing Masgo to have it removed, temporarily leaving her with only two Aspects.
After her death and reanimation the Battle of Liesse, she traveled through a portal to reach the pocket dimension where William of Greenbury was trying to summon an Angel of Contrition and Akua was trying to capture and kill it. Along the way, Chider, one of the claimants she had killed to take her Name and had been reanimated by Akua, arrived and used magic to usurp the Name of Squire. However, due to her lack of practice with the power granted by the Name Catherine was able to kill her and take it back. Because she had effectively just won the Name anew, she had a new set of three Aspects.
Powers
In addition to the remarkable strength of a Named, Catherine also has a few of other powers. After gaining the title Duchess of Winter she had her heart stolen by the king of winter (since returned) and replaced by ice she gained the ability to travel between creation.
Necromancy: She can raise and command undead animals, although she can only control one at a time and initially required a connection to be formed by personally killing any animal she wanted to raise. Although she used this power to create mobile explosives in her final exercise at the academy, she normally uses it to control an undead horse named Zombie and later Zombie 2. Her abilities with undead have matured with time. Allowing her to raise massive amounts of undead with her large reserves of power. Masego has commented on how her undead constructs appear with more life than they should. As of late she has noticed that the longer she keeps an undead alive the more intelligent it becomes. When she gathered eight mages, at first they only nodded their heads in answer to requests but in as little as an hour her undead were able to cast fireball spells. These are feats reserved for the undead of the Undead King, who was able to harness the powers of unnamed well after their death.
Fae Abilities: Glamour: She posesses the ability to make glamours that can be seen by everyone (the hero fight in Epilogue) or only affect one person (when she punished the captain of the Blackguards).
Her two previous Aspects, Learn and Struggle, were both of great value to her. Learn allowed her to quickly absorb information to consider later, which makes her a very good student. Struggle allowed her to tap more of her Name's power when she needs it the most in a losing fight. Catherine's third aspect was to be Seek, which appeared to be a Path-To-Victory-like Aspect, before it was corrupted by a demon and removed from her soul by Masego.
Her new Aspects, Take, Break, Fall appear to be quite powerful since she is able to take heroic name aspects as well as influenced by the King of Winter.
Take: Allows her to steal magical or Name-related power from others. When she Takes a magical power (example: from fae nobles) she can use their spells as if they were her own. When taking an aspect - like the Lone Swordsman's "Rise" - she can keep it even after its original owner's death, though she is bound by the same rules as the owner was. For example, Rise could only be used 3 times per day.
Break: Manifested after she broke the angelic sword into 100 pieces and scattered them across Callow. This aspect allows her to break both magical and physical things, from bindings to great palace doors.
Fall: Calls on the power of winter causing any thing in the affected area to be frozen, wither, and sapped of power. The effects are only effective for a limited amount of time.
Whether the original holder of an Aspect gets it back after having it Taken is currently unknown, as the only person to lose an Aspect was William, and he was killed immediately after.