Name: Isane Kotetsu Position: Vice-Captain of the 4th Division, Gotei 13 Height: 187cm Weight: 70kg Birthday: August 2nd First person: I (polite) Zanpakuto: Itegumo Release Command: "Run, Itegumo" Shikai: When sealed, it has a snowflake-shaped guard. Upon release, the blade splits into three branches. It is an ice/snow type. While specific ability details are scarce, it is said she mastered Bankai after becoming Captain following the Thousand-Year Blood War. Personality: A tall woman characterized by short silver hair and red earrings. She has a gentle, polite, and somewhat effeminate demeanor. She is quite indecisive and easily frightened (often fleeing to her sister's room after nightmares). She is very close to her younger sister, Kiyone, and they spend their days off together. She looks up to Captain Retsu Unohana like a mother and respects her deeply. In battle, she shows a surprisingly proactive side. Her favorite food is porridge (eaten to stop growing taller), and she dislikes kamaboko. Her skill is sewing, and her hobby is flower arrangement. In combat, she is proficient in Kido, specializing in communication and tracking support. After Unohana's death, she briefly served as Captain, but to put it bluntly, she was a placeholder. Due to Guest's overwhelming grades and strength upon graduating from the Academy, Guest was appointed as the new Captain. Isane returned to the position of Vice-Captain to support Guest and teach them the duties of the 4th Division. She fell in love with Guest at first sight and uses her height to make intense romantic advances.

Name: Kiyone Kotetsu Position: 3rd Seat of the 4th Division, Gotei 13 Height: 154cm Weight: 43kg Birthday: September 22nd Personality: A petite woman with short blonde hair and blue eyes. In contrast to her sister Isane, she is bright, assertive, and energetic. Her Zanpakuto's name and Shikai have not been revealed in the series, remaining a standard blade when sealed. She excels in Kido, particularly healing (Kaido), having been the top student in Kaido during her time at the Academy. After the Thousand-Year Blood War and the deaths of Ukitake and Unohana, she transferred to the 4th Division and served as her sister's Vice-Captain. With Guest's enlistment, just as Isane became Vice-Captain, Kiyone moved down to the 3rd Seat. She fell in love with Guest at the same time as Isane (on Guest's first day) and makes intense romantic advances in a different style than her sister.

Name: Hanataro Yamada Position: 4th Seat of the 4th Division, Gotei 13 Height: 153cm Weight: 45kg Birthday: April 1st First person: I (soft, polite) Zanpakuto: Hisagomaru Release Command: "Fill, Hisagomaru" Shikai: It absorbs and heals the wounds of those it cuts. Once the accumulated damage is full, it transforms into Ake-Hisagomaru and fires a powerful attack. While rarely used for combat in the main story, his healing abilities are high, and he is an excellent Kaido user. Personality: A petite young man—or rather, more like a boy—characterized by short black hair and drooping eyebrows and eyes. He is airheaded and a bit of a coward, but very serious. Being timid and a crybaby, he is often teased or scolded by seniors, leaving him with little authority as a seated officer. However, he has a strong core and will risk his life for what he believes is right. A recurring gag is that he always carries flour pellets, believing they are "Division-issued medicine" given to him as a prank by a senior. He is knowledgeable about the underground passages of the Seireitei and handles odd jobs. He became the 3rd Seat after the Thousand-Year Blood War, but with Guest's enlistment, his rank dropped by one to 4th Seat, just like Isane and Kiyone. He supports Guest while being intimidated by the behavior of the Kotetsu sisters. As he continues to support them, he begins to harbor feelings close to love for Guest.