Cécile Lafitte (セシル・ラフィット Seshiru Rafitto) is a teacher at Saint Marguerite Academy and the homeroom teacher in the section where Kazuya Kujo, Victorique de Blois and Avril Bradley is assigned to. Despite being part of Saint Marguerite Academy's faculty, she possesses a childish, friendly attitude and an interest in the supernatural.
Cecile is a small woman in her twenties with a baby face, fluffy brown hair and big round glasses. She is usually dressed in a light yellow blouse with ruffles dangling where the collar meets and a high-waist pencil skirt; she also wears a pair of Venetian-style loafers and white hosiery.
In spite of being a teacher of Saint Marguerite, Cecile does not necessarily exude an aura of a strict instructor. She is friendly towards other people, particularly the students of Saint Marguerite, and in fact, sometimes acts less mature than even Kazuya or Victorique, a tell-tale sign of her age; Cecile even suffers from being bullied by Victorique at times. However, she can also show a strict side, which actually managed to scare both Avril and Kazuya once.
As do most of the people in Saint Marguerite, she knows a lot of things about Sauville's many urban myths and has shared some of her knowledge to Kazuya; ironically, she is very weak when it comes to ghosts and anything scary, and would panic or faint when seeing or hearing scary things first-hand.
Before becoming a teacher in Saint Marguerite, Cécile was also a student in the said academy. Among her classmates was Millie Marl, who later became her close friend as well. When Millie Marl passed away, Cecile promised to take care of the primroses Millie received from Maxim, a promise she keeps up to the present.
At a later time, her father joined the First World War as a soldier. Her father's well-being caused Cécile to wish to leave the school and tend to her injured father, and during her last night in Saint Marguerite, unexpectedly became friends with Sophie, who was working as a maidservant in Saint Marguerite Academy's dormitories at that time.
The Wolf Cub Enters Saint Marguerite Academy
In the winter of 1922, Cecile receives an unusual package from Marquis Albert de Blois of Sauville. The Marquis entrusted the package, which he reveals is the "monster" named Victorique de Blois, and asks her to take care of Victorique inside the campus. After giving in to the Marquis' demands, she visits Victorique inside the house hastily built just for her, and to her surprise, she was demanded to appease the young girl's boredom.
A Grim Welcome for Kazuya Kujo
At the start of Saint Marguerite Academy's school year in Spring 1924, Kazuya was involved in the murder of a government official on the outskirts of the school premises. Cécile unexpectedly helps out Kazuya in escaping from an arrest ordered by Grevil de Blois by telling him to send handouts to a fellow student which stays atop the school's library tower. This would eventually open the opportunity for Kazuya to meet Victorique, who would later solve the case and clear Kazuya's name of any offenses.
The Mysterious Transfer Student
Cécile later becomes involved in the case regarding the discovery of a corpse inside the school's cemetery. She sees Kazuya with Avril Bradley, a newly-admitted transfer student from Britain, and after congratulating Kazuya for making his first friend, faints at the sight of the bony remains of a man dressed in a Knight Templar's armor.
After a quick recovery, Cécile tends to Kazuya after he was found unconscious in the school's abandoned warehouse while in search of a particular book. As Avril visits Kazuya in the infirmary, Cécile takes the time to visit Millie Marl's primrose garden located near the abandoned warehouse as part of her promise to her departed friend. Kazuya soon accompanies her and they had a short conversation about Millie and her death.
Kazuya later hears sounds from the nearby warehouse and decides to investigate. Cécile is reluctant to join him due to stories of the ghost of Millie Marl residing inside, but steps inside the warehouse anyway, although taking off her glasses from time to time to avoid seeing any spirits. However, instead of Millie's spirit, they hear a girl who appears to be asking for help. Kazuya later hears from Victorique that the girl is in fact the real Avril Bradley, and the Avril who introduced herself in class a few days ago was the successor of the notorious thief named Kuiaran. The real Avril was later rescued by Kazuya and Grevil and Cecile and Kazuya accompany her during her short recovery in the school's infirmary.
Watching Over a Sickly Wolf Cub
Due to a combination of cold weather and wearing a light garment such as a kimono at night, Victorique catches a cold. Cécile decides to watch over Victorique as she undergoes medication; meanwhile, Victorique laments that she would not be able to join Kazuya on his trip to Saubreme, the capital of Sauville. Cécile endures the day dealing with Victorique's childish rejections of taking in medicine through injection until Kazuya's return.
The Library Tower's New Visitor
Saint Marguerite Academy receives a donation of books from Jacqueline de Signore, Grevil's childhood friend and wife of the current chief of Sauville's police department. Cécile momentarily ushers the arrival of Jacqueline with her personal maid and soon leaves the two visitors under Kazuya's supervision.
Memories of Summer
As part of the school's regulations, faculty members are prohibited from leaving the school's premises during summer vacation, unlike most of the students who will be spending summer on their respective destinations. Victorique is also not allowed to leave the school grounds due to a different reason, and Kazuya decides to stay to accompany Victorique.
- She is 168 cm tall (5 foot 5) and 174 cm (5 foot 7) with heels. Her weight is 54 kg (118 Ibs.)
- She also reveals that she has been best friends with Sophie, and has visited a certain store in Saubrème on their trips together.
- Cecile was based on a friend of the author's, who works as a middle school math teacher. According to Sakuraba, this friend of hers is very popular with her students, but also has a weird side to her.
- "Oh, you recognized them (primroses). A friend of mine (Millie Marl) loved them." — Cécile to Kazuya, during a conversation near Millie Marl's primrose garden, GOSICK Manga Chapter 3
- Gosick Volume I Afterword