Kurumi (くるみ, Kurumi) is a young woman who is an itinerant martial artist along with her older sister, Natsume. For years the two wandered Japan in search of their long-lost father, Soun Tendo. They briefly usurped Akane Tendo and Ranma Saotome’s claim to inherit the Tendo Dojo and carry on Anything Goes Martial Arts after challenging and defeating them, but conceded their claim following a rematch.
Kurumi has chin length brown hair that she wears higher by using a very long red ribbon that also functions as her weapon. She has dark brown eyes and typically wears a white sailor suit uniform with a blue collar, red ribbon, and blue skirt. Her training outfit is a short-sleeved light pink jumpsuit secured by a red sash around the waist. When she was younger Kurumi wore her hair in a similar manner and also used a similar training outfit. She is shorter than Natsume and about the same height as Akane.
As the younger of the two sisters, Kurumi is the opposite of Natsume. She can be characterized as being warmer, and her personality and attacks appear to be associated with fire. Kurumi is more personable, kind-hearted, and empathetic, but is also more childlike. She is also known for her enormous appetite.
Natsume was found 18 years ago in a pile of sand near a shrine and was adopted by the priest. Two years later Kurumi was found there as well. Since the two had the same medallion the priest theorized that they must be sisters. So every year he took the two back to the spot in case someone was there. Eleven years ago despite the priest being ill the two decided to go to the spot by themselves when they were attacked by a bear. However they were saved by a passing martial artist, who they believed to be their long-lost father. This stranger, later revealed to be Happosai, told them that when they became true martial artists they would inherit the Anything Goes School of Martial Arts. Two photos were taken of him with the sisters. One, which showed the three side by side, was kept by Happosai. The other, in which only his back was shown wearing his gi with “Anything Goes Martial Arts” written on the back, was kept by the sisters. On the back of this photo Happosai wrote that they would carry on the school when they were older and signed it as “Soun Tendo”, with the intention of giving them a goal to strive for. However he never told Soun about this promise. Since the girls were young at the time, they had forgotten what Happosai looked like and had grown up believing their father to be a heroic, larger than life figure.
Since then, the two traveled throughout Japan, largely living a nomadic existence, although their use of school uniforms suggests that they were enrolled in school at some point. They eventually end up in Furinkan, where, with their money having run out, they resort to a series of food thefts in order to eat. Kurumi’s ribbon comes in handy, and the pair hits Okonomiyaki Ucchan's, Shampoo on a delivery accompanied by Mousse, and later Ryoga Hibiki and Tatewaki Kuno. Because of their speed and Kurumi’s ability to eat any quantity of food in a matter of seconds, the food thieves’ identity cannot be determined.
However they reveal themselves when Akane Tendo is walking home with some food from a local restaurant. Kurumi is ravenously hungry, but Natsume stops her from grabbing the food out of Akane’s hands, allowing her to accept when Akane offers it, and Kurumi consumes the sushi in 2.22 seconds. The pair then thank her and follow her home, despite her efforts to lose them. In the living room, Kurumi tries to help herself to the snacks that Kasumi offers them, but is stopped by Natsume. After Nabiki comments on their manners, the pair then introduce themselves, Natsume explaining that they were driven to steal food when they ran out of money and now desire to pay Akane back for feeding them. After hearing their story, Soun offers to host them for a while, which they accept.
While talking in Akane’s room, Kurumi readily lifts one of her 10 kg dumbbells. Akane learns that the two are martial artists and searching for their father, who they believe to be a powerful martial artist. Natsume readily takes her up on her offer to spar with them, and Kurumi somewhat reluctantly agrees, although she ends up being the one to fight Akane. After Ranma tells Akane that this is a bad idea, Kurumi also asks her if this is okay, but to save face Akane pushes ahead anyway. During the fight, none of Akane’s attacks can touch Kurumi, although she just dodges. Akane then launches a flying kick at her that misses, but loses control and threatens to slide into some training equipment. Kurumi however swiftly whips out her ribbon and ensnares Akane to halt her momentum. After apologizing that she had to do this to save Akane, Kurumi is thrilled when Akane offers to cook for them out of gratitude. Akane cooks half of dinner and before Ranma can warn Kurumi not to touch it, she eats a vast quantity in seconds to everyone but Natsume’s amazement, asking for more.
After dinner, Soun asks how Akane and Kurumi’s sparring match went. Kurumi hesitates to answer, leading Nabiki to respond that she was a pushover as Akane is only doing martial arts these days to avoid dieting. When she comments that the heir to Anything Goes Martial Arts is useless, Natsume reveals that their goal is to be the best in what they call Anything Goes Female Martial Arts (Women’s Anything Goes Martial Arts in the dub) to fulfill a promise made to them by their father, Soun Tendo. When Soun reveals that this is his name, the pair calls him father and Natsume pulls out the photo of the three of them together to prove it, as Soun cannot recall ever having illegitimate children. After telling their story, she points out the promise written and signed on the back, which appears to settle things. When Kurumi hugs Soun again, he tries to ask Nabiki and Kasumi for help, but they do not believe him.
Beginning the following day, both sisters begin to spoil Soun and Genma Saotome, preparing their meals, keeping them fed, and even offering to wash their backs while they are soaking in the furo, with Kurumi washing Genma’s back. That afternoon when Genma suggests that they leave the dojo to Soun’s new daughters, Akane disagrees, but the idea is supported by Natsume, who suggests that only the best fighter in the family should be the one to pass on the school, and that she and Kurumi are the more appropriate heirs, not her. Kurumi opposes this, but after Akane suggests that they see if they are stronger than her, Ranma accepts the challenge in his female form, and Natsume agrees to take them both on. Kurumi is upset at this turn of events, but does not say anything and goes along with her sister.
Prior to the fight, Natsume tells a reluctant Kurumi not to hold back. When Ranma charges in, Kurumi uses her ribbon to beat him back, leaving him with a burn on his left forearm. Natsume then targets Akane with a wind slash and then an ice tornado, causing concern for Kurumi. When Ranma and Akane argue, Natsume has Kurumi initiate the Ring of Dragon Fire to finish them off, although she herself eases up on her part of the attack to avoid injuring them. Kurumi feels badly for how Akane takes the loss and does not share her sister’s exultation in their victory.
When Soun discovers where Akane has gone, Natsume asks Kurumi where he is. Later while Natsume is practicing in the dojo, Kurumi, who had earlier seen Akane out running, speculates that she will be returning soon for a rematch. When Natsume vows to fight any challengers, Kurumi suggests that Soun might not be their father. However Natsume is adamant that he is, citing the signed promise on the back of the photo. She tells Kurumi to practice so that they can defend the dojo, and the pair proceeds to punch holes in the wall, which a crying Soun patches up.
On the day of the rematch, Natsume was originally to fight Akane first, but Kurumi asks to be the one to take her on, claiming that she wants to finish her off. This time the two are more evenly matched, although neither is able to land any hits. Kurumi then uses her ribbon to grab Akane by the right forearm, but the latter counters by charging, nearly landing a counterblow. Natsume then tells her to trade places, claiming that where one ends, the other begins. However Ranma then appears to make it a two on two fight. Natsume launches an immediate attack by using Kurumi as a springboard to leap into the air. Akane tries to take her but is edged out of the way by Ranma, who is tripped up by Kurumi’s ribbon, allowing Natsume to knock both of them down. However Ranma jumps back to avoid Natsume’s wind slash and jumps over her tornado attack. Kurumi then uses her ribbon to force her back. This time Kurumi launches the Ring of Dragon Fire attack first. In response, Ranma has Akane run into the spiral and fires a horizontal version of the Hiryu Shoten Ha to counter it. This cancels out the Ring of Dragon Fire and propels Akane at the pair, allowing her to take them both out with the Lightning Splits Attack.
Kurumi recovers first as she was not knocked out, unlike Natsume. However the sisters then learn that Happosai was the one who rescued them years ago after he appears and that they were misled all this time. After they kick him through the roof, the pair decides to leave, vowing to train themselves until they are strong enough not to bring shame to Anything Goes Martial Arts, when they will return to challenge Ranma and Akane again. However Kurumi is the only one to take one final look at their hosts before leaving.
The two came across Ranko Kuramitsu as she was practicing in the park after initially mistaking her for Ranma’s cursed form. She offered them lunch and when they noticed that the symbol on the back of her jacket was the same as the one on their medallions. When they asked her about it she explained that it was the logo for my parents’ company: Kuramitsu Sol.
Both sisters are stealthy and very fast, which allowed them to steal food from five talented martial artists and escape detection. Their version of Anything Goes Martial Arts has a little bit of what Happosai taught them, but is largely of their own invention. It places an emphasis on fighting together, making them a formidable combination by mutually supporting each other. Natsume specializes in close range fighting, while Kurumi uses her ribbon for distance attacks to set opponents up for Natsume or drive them back. However each sister is a competent martial artist in her own right. Kurumi has decent hand to hand skills and was better than Akane until the latter underwent some intense training to get up to par. She is very accurate with her long ribbon, which she uses either as a whip or to entangle opponents, targeting their arms or legs. She can charge the ribbon with hot energy to create a burning effect.