Kururu Sumeragi is the leader of the current Tool Toul To and Kings and Roads. She is also Canon's cousin and Ikki's tuner. She has very messy hair, and uses pins in attempt to keep it kept. She always carries tools around in her clothing. It is noted that she has a tattoo of Tool Toul To's emblem below her left ear but whether this is because of her station as the Pledge Queen, or because she is a member of Tool Toul To (implying that all members have a similar tattoo), or if it is personal choice hasn't been seen.
Kururu is a young teenage girl of average height with long light colored purple/pink (depending on source) hair that goes down to her back and has some sides of her hair sticking up, which she can't keep smoothed. Her friends call it cute. She usually wears her Tool Toul To outfit or her school uniform and has a hair pin at the top of her head in the shape of an X.
Kururu is a very kind, compassionate, innocent, cheerful, and polite person. She treats others with respect and treasures her friends and family dearly and is willing to do anything for them. Such as when she was torn between being with her father or Ikki whom she developed feelings for and wishes to be his Link Tuner.
Kururu is also very forgiving, such as when Hako Isawa tried to attack her and even stole her tools to make the Storm Regalia, Kururu held no resentment nor hatred towards her and even didn't even cared when she was stabbed in the hand by her. However, Kururu is serious and forceful when she needs to, such as when she told Hako who the leader was and ordered her to do as she's told, knowing when to put others in their place. She is very loyal to her team and considered them to be apart of her family.
Being a member of Tool Toul To, Kururu has a habit of having a large amount of tools on hand that can never been seen on her body and can create and take apart any device in mere seconds, greatly impressing others. This is somewhat a gag, as others wonder what she does with her free time and how does she have so many tools on hand.
Kururu, like Simca and Ringo, has feelings towards Ikki, which develops into love (like Simca and Ringo). She cares for him and admires his compassion toward his friends such as when he cried over Simca's condition and Sora's betrayal, she held him. She even wishes to be his tuner on more than one occasion. However, despite her feelings towards him, she respects him enough to let him choose who he wants to be his Tuner, such as being ok with Ringo being the Tuner for him and even lied saying she only respects him as a rival. However, she confirmed to her team that while she still loves Ikki, she doesn't want Ringo to know.
Originally, Kururu aims to be Ikki's Tuner and wants to get to know him better personally and in order to tune him better. Although shy around Ikki at first, she becomes devoted to him after witnessing his anger over Simca's attack. She does not wear A-T's, but as the leader of Tool Toul To, she is a true genius in repair, construction, and maintenance of A-T's. In Ikki's battle with Ringo, Kururu identified the sound of Ikki's A-T's, arrived at the battle in time to intercept Ikki as he was falling toward the river, and rebuilt his ruined A-T's in midair in less than three seconds. She originally rebuilds the Wind Regalia for him, though it is stolen and given to Sora. During the Fight with White Wolf Clan, Kururu wants to show Ikki her power as a Tuner by helping out the other team. Afterward, Ikki asks her to create the new Storm Regalia for him, a request which she gladly accepts.
It quickly becomes evident that Kururu cares deeply for Ikki. During the talk with Kilik and betrayal of Sora, she ran to him and tried to comfort him. Later on, she appeared along with Simca and Ringo (under the guise of Croissant Mask) after Kogarasumaru's special training. Agito teases them, saying, "You three came here with intentions of getting a kiss, but you're out of luck, right?" The three deny this accusation, but then reveal they had some similar intentions. During that time, her power struggle with Simca and Ringo over Ikki's attention is seen.
As of chapter 264, Kururu has assembled the masse of Tool Toul To and is planning to use the Infinite Scale to complete the Storm Regalia en route to Kogarasumaru's position on Sora's aircraft carrier. It can be implied that for the time being Tool Toul To has allied itself with Kogarasumaru instead of remaining neutral. Later on, U.S. President-Elect Omaha (in Emily Adachi's body) informed Ikki that Kururu could no longer become his Tuner, as she sacrificed herself, using her sound to keep the tuning system in the ship alive. Konomi offered Kana to be Kururu's temporary replacement, but Hako interfered; however, Ikki chose Ringo instead, telling her that she has always been closest to him. Following this revelation, Hako protests, as Ringo doesn't know what to do. As the argument began to worsen, Kururu (being bound to the ships mechanisms) sent out a projection of herself using the ships's optical systems to intervene. Her projection reveals that she could not be the Tuner and instead will put her full attention to creating the Storm Regalia, "risking her life in the process" and went on to state to Ikki that she considers him her greatest rival whom she respects and admires. Admitting she does not want to lose Ikki, Kururu will give her all in this fight, in her own way. This left Ikki to affirm his selection of Ringo as Tuner. Seeing Kururu give up her position as Ikki's Tuner firsthand, Hako is further saddened and enraged; her jealous claim that Kururu could have everything she wanted (in this case, Ikki) had just been refuted.
Kururu, along with the other Tuners, start the tuning process with Ikki and Ringo. Suddenly, in the middle of the process, a cable almost wears out. Hako and some of the rest of Toul Tool To manage to fix it in time. Kururu states that she is thankful to have friends like them and that she'll continue fighting with them until the very end.
During Ikki's battle in the Tower, Kururu is seen recovering in a sort of sick bay aboard one of the planes. She appears to be overheated, as ice packs cover her. She tells Emily and others that anything can be done for those they love. Konomi picks up on this and teases Kururu for her still existing love for Ikki. Kururu commands Konomi not to tell Ringo about what she said.
Currently at Chapter 353, it was revealed that Kururu implanted the Storm Regalia inside the Thorn Subregalia of Ringo.
Kururu is the current Pledge Queen of the Ring Road. Although she is not a Storm Rider, she is still considered Queen-level for her skills with tuning. Numerous characters on all sides of the war between Sleeping Forest and Genesis have remarked that she is Ine Makigami's successor. Like the other Kings and Queens, she has her own 'shadow', consisting of a singing woman draped in piano mechanisms, which first appeared in Chapter 104.
As the Pledge Queen, Kururu is able to activate the Pledge Regalia. It takes the shape of a large cross (larger than Kururu herself) which splits into numerous, thinner crosses interconnected by a large amount of wires. By synchronizing their movements through singing (characterized as bird calls by onlookers), all Tuners connected to Axis are able to access Kururu's immense tuning prowess, including Infinite Scale.
Infinite Scale - As the Pledge Queen, Kururu is able to access the world of "Infinite Scale". This enables her to repair, modify and/or tune any A-T's in a matter of seconds, if not faster, though she cannot repair something that is torn apart, such as the bullet hole shattering a chunk out of the original Storm Regalia core. Other members of Tool Toul To have remarked that this level of repair work is actually painful to the eyes and hands, although Kururu has shown none of these side-effects.
- Construction - Using a number of tools she keeps on her person at all times, Kururu is capable of repairing any A-T based technology. During Ikki's fight with Ringo, she was even able to repair and install a Wind Sub-Regalia in midair under three seconds .
- Destruction - During the battle at Genesis headquarters, Kururu demonstrates the ability to detune and destroy A-T armor with her tuning abilities. Through the usage of the Pledge Regalia, other Tuners can perform this same feat, making it a formidable tool in battle.
Pledge Regalia: Access - Kururu activates the Pledge Regalia, splitting it into numerous thinner crosses that enable other Tuners to access Infinite Scale.
Ring Road: Ring In - After activating her Pledge Regalia, Kururu synchronizes with the Tuners connected to the Pledge Regalia through song, which in turn enables them to use the highly efficient tuning abilities of Infinite Scale.