Meguro, whose real name is Koto, serves as a kunoichi in the Rokki-dan under Habaki Kagimura's command. She possesses an emotionally volatile temperament marked by pronounced jealousy, particularly directed at Rin Asano and her comrade Tanpopo. This jealousy stems from Meguro's infatuation with the painter and ninja Master Sori, from whom she receives painting lessons alongside Tanpopo. Meguro frequently resents Rin after Rin moves into Sori's residence, fearing Rin will divert Sori's attention. She also envies Tanpopo's physical appearance, often insulting her with derogatory remarks like "pig" due to Tanpopo's larger bust size. Meguro is equally dismissive and insulting toward Magatsu Taito, initially unaware of his Ittō-ryū affiliation.

Her narrative involvement begins with the Rokki-dan before she studies painting under Sori. When Rin brings Manji to Sori's house, Meguro's jealousy intensifies, disrupting her desired time alone with Sori. She participates in espionage, spying on Ugen Hanabusa during surveillance of Kagimura's family. While tailing the Ittō-ryū's departure from Edo, Meguro and Tanpopo notice Anotsu Kagehisa's absence and attempt to rendezvous with him. Ambushed by shinobi sent by Hanabusa, Tanpopo is injured by shuriken; Meguro sustains a self-inflicted arm wound fending off attackers before escaping with Tanpopo. Rin later finds them and secures medical aid from Burando.

Confronted by Shira demanding information on Manji and Rin, Meguro, following Kagimura's survival advice, reveals their location. She later returns with Tanpopo to aid Manji and Rin against Shira. Meguro engages Shira directly, exhausting herself as her attacks prove ineffective. Shira overpowers her, partially disrobes her, and mocks her physique before Magatsu sacrifices himself to save her. Meguro later aids Rin by warming her after Rin's rescue from freezing water and intervenes when Renzo Kawakami attacks Manji, throwing Renzo to the ground. She and Tanpopo accept responsibility for Renzo's care. Three and a half months post-conflict, Renzo resides with Sori studying painting, fueling Meguro's persistent jealousy over Sori's attention toward Renzo.

In combat, Meguro wields a small blade and utilizes foot spikes for mobility. Magatsu Taito notes her exceptional agility, comparable to Dōa Yoshino, despite her physical weakness. Her dialogue reflects her fiery personality and insecurities, featuring quotes like "Rin-chan brought a man home! That horny little brat," "Silence, pig!!," and declarations such as "And... and... and I'm a virgin! Oh, God! I said it!" highlighting her emotional outbursts and vulnerability.