Princess Donut and Katia Grimmsdottir become friends while fighting alongside Carl in the dungeon. Katia first joins Carl and Donut as a comparatively inexperienced crawler entrusted to them by Hekla. Their partnership survives Hekla's attempt to use Katia against Carl, and it continues after Katia begins leading a separate group. The Enchanted Crown of the Sepsis Whore later places both women in the Blood Sultanate's royal succession, threatening to make their survival mutually exclusive on the ninth floor. Neither accepts the contest the crown appears to impose. Their efforts to escape it culminate in Katia's departure from the dungeon and Donut's descent with Carl.
Katia joins Carl and Donut
Donut meets Katia when Hekla asks Carl's party to help her gain experience. Katia is much lower in level than Carl and has difficulty controlling the appearance of her transformed body. Donut greets her openly, asks about Hekla, and speaks admiringly of the woman Katia credits with saving her life. Hekla's request is practical: Katia can join Carl and Donut's party, share experience, and learn while being kept away from the worst danger. Katia is initially Hekla's friend and responsibility, but living and fighting with Carl's party gives Donut a relationship with her that Hekla does not control.
The arrangement becomes more than training when a failed spell threatens a broad area with an explosion. Katia cannot use the escape route Mordecai recommends for Carl and Donut: she lacks access to the Desperado Club and, as the host of a quest, cannot retreat into a saferoom. Donut immediately objects to leaving her. She reminds Carl that they promised to keep Katia safe and later insists through party chat that they cannot abandon her. Katia, meanwhile, tries to move the nonplayer residents back into their homes and tells the others to run. Donut's concern arises before she and Katia have known one another long. Carl recognizes that Donut is honoring a promise to someone she scarcely knows, even while Donut partly deflects his praise by mentioning how Hekla would react if they failed her.
Katia also begins to participate in decisions that affect Donut directly. When the Sepsis Crown becomes dangerous, Carl urges Donut to remove it; Katia agrees with him. Donut yields reluctantly. The item disappears, but its later consequences are not erased by removing it. That small exchange shows Katia acting as a member of the group rather than merely a person under its protection. On a subsequent appearance with Odette, Donut notices that Katia has become much more skilled at shaping her face. Katia's black-haired appearance is her own, and Donut compliments it. Their ease with each other has grown alongside Katia's abilities.
Partnership in the Iron Tangle
The Iron Tangle makes the three crawlers depend on different strengths. Katia can change her shape and carry great weight; Donut supplies spells, ranged attacks, and Mongo's help. During their first dangerous train ride, Carl asks Katia to enter a car ahead of him because her constitution is far higher than his. She is frightened but agrees. Donut assures her that the others will support her. When Mongo knocks Katia down in his eagerness to attack, Donut scolds him and tells him to be kind to her. The incident is minor beside the monsters on the train, but it shows Donut treating Katia as a teammate whose place Mongo must respect.
At a station crowded with hostile creatures, Katia closes doors to keep the attackers out while Donut illuminates the train car and attacks with magic. Donut moves onto Katia's shoulder during the fight. As the party tries to hold the car, Katia watches the route and reports approaching stations while Donut prepares traps and follows Carl's rapid instructions. Katia is still shaken by the violence she sees; Donut's response is blunt, reflecting her own hardening in the dungeon. They are fighting the same battle, but they have not reached it with the same experience or temperament.
Their cooperation extends to planning beyond the immediate fight. Donut and Katia train in the upgraded personal space, and both help examine the locked route toward an engineer's car. Later, while Carl plants explosives on a train, the two women send rapid-response carts through portals. After Hekla's death, Katia and Donut share a laugh at Carl's determination to rescue yet more crawlers, even though Donut has just challenged whether the party can save everyone. Donut ultimately accepts the risk. Katia is no longer simply catching up with the others; she helps operate the group's machinery and make its rescues possible.
Hekla's attack and Donut's choice
Hekla's arrival tests the difference between Katia's original allegiance and the trust built in Carl's party. Katia has allowed Hekla's daughters into the group's personal space. Hekla thanks Carl for training her and describes Katia as someone she has come to collect. Donut, who admires Hekla, initially welcomes the idea of closer cooperation. Carl is more suspicious. The party has reason to consider Hekla an ally, and Katia's connection to her is real; this makes the coming betrayal especially damaging.
During the joint train operation, Hekla attacks Katia. Eva, another of Hekla's daughters and an old friend of Katia's, also turns on Carl and Donut. Donut sees that Katia has been deliberately shot and rejects the claim that it was an accident. Hekla tries to halt the fight and frame the attack as a mistake that the groups can set aside. Donut refuses. She accuses Hekla of making Katia feel valued only to use her. Katia wakes disoriented and initially recalls Donut's magic missile hitting her amid the battle; Donut insists that the real attack came from Hekla. Eva's explanation that Katia was being used to provoke Carl confirms that Katia was an instrument in their plan, whatever assurances Eva offers about their intentions.
Donut's reaction is personal as well as tactical. She tells Katia she may stay with them and promises they will not abandon or deceive her. She also says Katia did nothing wrong and had tried her best. Carl realizes that Donut's anger reaches beyond the immediate attack, although his recognition does not give him time to resolve it during the confrontation. For Katia, Donut's defense supplies an answer to Hekla's attempt to make her expendable. Donut is willing to break with someone she had praised because of what that person has done to Katia.
Hekla dies as the confrontation worsens. When Eva attacks Katia afterward, Donut uses her magic on Hekla's body to create clockwork copies that drive the attackers back. Katia, despite being the target, pleads for the other daughters to be spared because they do not know what Hekla and Eva planned. Their different responses fit the same objective: keep Katia and the other crawlers alive while stopping those who initiated the attack. The shared ordeal changes their bond without making their temperaments identical.
Separate parties and a shared threat
Katia later works with crawlers outside Carl and Donut's immediate party. Separation does not make her absence trivial to Donut. On the sixth floor, when Donut fears that Carl's increasingly dangerous choices will leave her alone, she specifically tells him that Katia has left them. Her words are an expression of abandonment anxiety, not a claim that Katia has become an enemy. Katia remains part of the larger network of allied crawlers, and Donut continues to communicate and cooperate with her.
The crown makes their friendship vulnerable to a rule neither of them chose for the other's sake. Donut had worn the Enchanted Crown of the Sepsis Whore earlier in the crawl. Taking it off did not remove her from the Blood Sultanate's royal line. Its rule bars a royal wearer from descending beyond the ninth floor until the sultan and the other royal members have been killed. Eva later places a crown on Katia immediately before Eva dies. When Katia shows it to Donut, Donut first admires the purple tiara, then understands what it means. The problem has moved from a distant obligation Donut feared for herself to a direct conflict between two people who love each other.
Donut identifies the apparent purpose immediately: others want her and Katia to fight. She compares the pressure to earlier attempts to turn people close to her into sources of spectacle or pain. Katia promises she will not fight Donut, even if refusal costs her own life. Donut tells her she feels the same, but asks the necessary question: if only one royal heir can descend, how can they both leave? Their exchange is unusually explicit about the stakes. Neither mistakes affection for a mechanical solution. Katia has been seeking one, and she reveals an item obtained from her celestial reward: a locked box holding the Orchid of Eileithyia's Grace. The possible way forward depends on opening and using the orchid, not on persuading the crown to forget either wearer.
Katia's distress during the search for a solution is visible to Donut. When the group finds Katia crying in the Desperado Club, Donut rushes to her and presses her head against Katia's. Katia also risks herself in the club as the group pursues the plan involving Astrid; she tells Carl that she will not give up on him or Donut. The crown's rule has made her survival a collective problem, but Katia does not withdraw from the others while they work on it.
The ninth floor and Katia's departure
On the ninth floor, the group must eliminate the Blood Sultanate's nagas before either woman can descend. That requirement is distinct from the remaining problem: with both Donut and Katia in the succession, victory over the nagas alone does not free them both. Katia's proposed escape uses the orchid and Eileithyia's intervention to remove her from the ordinary descent. An arrangement with the goddess's sponsor, Huanxin Jinx, appears to offer Katia a place as a celestial attendant on the twelfth floor. Carl also knows the orchid could lead to pregnancy and removal from the dungeon, or to a constitution enhancement that would leave the crown's conflict unresolved. The outcome is uncertain before Katia makes her choice.
Donut and Katia continue to work together while the plan approaches. Katia helps charge Donut's new tiara by placing enchanted headgear on its pillow, and the two share an ordinary moment with Mongo and Rend shortly before the final crisis. Carl sees them together and thinks about the impending separation. Their friendship persists as a practical collaboration and as companionship; the orchid does not reduce Katia to a piece in a rules puzzle.
The final countdown leaves little room for the farewell Donut expects. When Carl orders Katia to eat the orchid, only slightly more than the hour required for its effect remains before the floor's destruction. Donut protests that she has not had the chance to say goodbye properly. Katia is worried about possessions she has not transferred, but consumes the orchid and becomes unconscious before Donut can speak with her. Donut stays beside her and fears she may never get another chance. Her grief is sharpened by the uncertainty of whether the group's plan will work in time.
When Katia wakes, Huanxin arrives in Eileithyia's form and tries to hurry her decision. Donut challenges how Huanxin speaks to Katia and says her friend does poorly with such treatment. Donut then uses her enhanced Laundry Day spell to pull the sponsor out of the goddess's protection. She confronts Huanxin over treating Katia's danger as an opportunity for exploitation. Katia has given Donut her crossbow and a celestial item that Donut can wear; those transfers become part of Donut's attack. Mordecai loads a bolt into the crossbow, and Donut kills Huanxin. Their victory is a coordinated act against the person attempting to control Katia's choice, not an attack on Katia herself.
Katia still has to choose. After the group embraces her, Donut admits she is frightened they will never meet again. Katia asks Donut to keep Carl safe and chooses to be made pregnant, explaining that it will send her out of the dungeon. She intends to help children on the surface who need protection. Donut supports that purpose when Eileithyia questions it. The goddess accepts Louis as the human father and restores Katia's human form; the restoration reveals injuries Katia's transformed body had concealed. The others attach prosthetic parts Katia prepared in advance. Once the pregnancy is complete, Katia becomes ineligible to continue the crawl and disappears. Donut says goodbye after she is gone.
Donut then descends with Carl. She tells him she will miss Katia, and resolves not to let those who engineered such pressures break her. Their parting fulfills the promise Katia made when the crown was revealed: the two do not fight each other. Katia's departure removes the conflict between their claims to the ninth floor's royal succession, while leaving Donut to continue without a friend who had been with her since the early floors.
Concern after separation — Book 8 spoilers
The separation does not end Donut's concern for Katia. On the tenth floor, Donut asks Lexis for news from the surface and specifically whether Katia is safe. Lexis says information from South Asia is limited, but her contacts have communicated with Katia; she believes Katia is all right. Her report also points to an unexplained protector at the facility. Donut presses for reassurance, yet the interrupted conversation does not establish everything happening around Katia. The scene shows that Donut still treats her friend's safety as an immediate question, not a settled consequence of leaving the dungeon.
Later, as Louis prepares for danger, Donut reminds him that he is the father of Katia's child and urges him to be careful. The remark is partly teasing, but it also connects her concern for Louis to Katia's life outside the dungeon. The two women do not reunite in these scenes; their relationship continues through Donut's questions, concern, and attention to the people Katia left with the group.