Kaoru Umemiya

is a member of the Ishiyama High School's Red Tail, a group of strong female students who are entrusted with the protection of Ishiyama High's female students.

Appearance
She is a girl with short purple hair. She wears a standard school uniform and, like Nene Ōmori, she is always seen wearing a white coat. She is also notably the tallest member of the Red Tail.

Personality
She is usually the most silent and reserved member of the group and seems to keep her composure in most situations and is usually the most serious of the group, a trait she shares with fellow Red Tail Ryōko Asuka. Unlike the other Red Tail, she and Ryōko are the only ones to not have befriended the 3 male members of the Tōhōshinki and their subordinates and are still the only ones to hold a negative view on men, however she did show some regret at not having been able to join in on the fun during the War Games incident. Like the rest of the Red Tail, she thinks little of Furuichi, believing him a perverted lolicon.

Field Trip Arc
Ryōko later accompanies her fellow Red Tail to the local river, where they are joined up with several of their peers.

Return to Ishiyama High School Arc
On their first day back in Ishiyama, Umemiya and the other Red Tail girls meet up at the rooftop of one of the buildings, where it is revealed that Yuka does not really know about the "Killer Six Elements" yet. Umemiya tells her friend that she needs to pay attention to the rumors more often. She then sits out and listens as Nene explain about them more clearly to Yuka.

Later on, a meeting is called at the Kunieda residence regarding the "Killer Six Elements", which Umemiya attends.

The next day, Umemiya hangs out with Ryōko while the other delinquents gather information on the Poltergeists. At some point, they learn that Oga and Kanzaki have both defeated Nasu and the Poltergeists respectively. Yuka soon rushes to them and shouts out about how she saw one of the Poltergeists' face melt away. Umemiya is skeptical of this and explains about the recent fight between Oga's and Nasu's parties, then telling her to pull herself together. She then mentions how they only need to worry about the "Reborn Red Tail" now before inquiring from Ryōko about Ringo's personality. To their surprise, they are told that she is simply a "witch".

The three are later told by Furuichi that Aoi is supposedly going to fight Ringo; both Umemiya and Ryōko are particularly unsurprised at the situation. However, they become excited when they see Nene appear and happily agree to accompany her to the front lines. As they stroll the hallways, they are confronted by the "Reborn Red Tail". Both generations then clash with one another; unfortunately, all members of the Red Tail are badly beaten and defeated.

They are subsequently taken to a desolate area within the school with Aoi and Ringo inside. Upon their arrival, Ringo proposes that Aoi fight either Nene or Oga for the other one's safety or otherwise be beaten along with all of them. Umemiya screams for Aoi to fight back.

Later, in the midst of her fight, Aoi proclaims that she will return to being the leader of the Red Tail again; hearing this causes Umemiya to smile. She is later released from her hostage position, surprising her. Umemiya then watches as Ringo threatens to burn off one of Oga's eyeballs, catching Umemiya off guard. Not long after, she then launches a very powerful attack towards Oga, which, although it missed, astonishes Umemiya. She then warns Aoi to be careful while fighting Ringo again.

Powers & Abilities
She wields a wooden sword to fight her enemies.

Trivia

 * In the anime when she first appeared with the Red Tails on the assault on Ishiyama High to confront Tōjō, her hair is coloured light brown instead of purple.