Kumokawa Maria is a character introduced in Shinyaku Toaru Majutsu no Index, as Kumokawa Seria's younger sister. Seemingly a background character as a maid-in-training of Ryouran Maid School and friend and classmate of Tsuchimikado Maika in her first introduction.
She is reintronduced as a during the Natural Selector tournament, where she receives reports that Kihara Kagun, her beloved missing teacher would be there. She later gets caught up in the experiment of Othinus in Baggage City, and the bloodbath that ensues in the battle between the Kiharas and Academy City forces and GREMLIN and the Baggage City forces, and tries to survive. She is arguably the main heroine of the 4th Shinyaku Toaru Majutsu no Index Light Novel Volume.
She is cheerful, confident and prideful due to her abilities and talent as a maid are superior. Her goal is to find and service an incompetent and stupid master; to do this she works her pride to be damaged to a level where it will not break.
She also has a strong sense of justice, helping people who are a threat to her life, not allowing Shuri to kill people, and even merely subdued Kihara Enshuu even after all she had done to her. She is referenced as someone similar to her sister, as someone who could not do not do anything to prevent terrible things from happening despite knowing about it.
Furthermore, she is greatly acquainted with scientific principles, analytic, and is pragmatic, allowing her to solve situations without needing any special powers or assistance. For example: using her maid outfit to cause a dust explosion, as well as using a blowdryer to destroy "bugs". She is also determined, going all the way from Academy City to Baggage City just to find a single person. Moreover, she has one of the best grades in her school, and the narrative states her as a transcendent genius.