|Other Names, etc.||Ryoko Tamiya|
|Japanese||田村 玲子 - 田宮 良子|
|Rōmaji||Tamura Reiko - Tamiya Ryōko|
|Age|| 31 (Early - As Ryouko Tamiya)|
32 (At the end - As Reiko Tamura)
|Relatives, etc.|| Mother (Human - Deceased) |
Mr. A (Mate - Deceased)
Gotou (Creation - Deceased)
|Occupation||High School Teacher (Former)|
|Anime debut||Episode 3|
|Manga debut||Chapter 5|
|English Voice||Joanne Bonasso|
|Live Action||Eri Fukatsu|
In Reiko's first appearance, she had shoulder-length light purple hair and sharp brown eyes with bags underneath them. She had an average height and a slim build. Students would comment on her good looks.
With her second appearance, her body type remained the same, but her skin became fairer. She now had long black hair and a more pointed face. Her expression changed to one that was calmer and relaxed. She was often seen wearing formal attire and lipstick.
Reiko was a highly intelligent parasite with scientific inclinations and a drive to discover the biology, origin, and purpose of parasites. She often studied the human psyche alongside her examination of her own species. Although initially just as cruel and unfamiliar to human psychology as her fellow parasites were, she slowly grows to understand human emotions and reactions.
She is more logical and reasonable than many other Parasites and allows Shinichi Izumi to live unmolested largely because she finds him an interesting anomaly worthy of study, despite other parasites instinctively thinking him a threat. Even when threatened by her own species, she is more interested in the fact that parasites are developing further and further from the blank slates they began as.
She is quite manipulative, capable of using her studies on human and parasite psychology to predict reactions and steer individuals towards her own aims. She is also aware of her own higher capability over most other parasites, as seen when she mocks Kusano and his teammates for believing they could beat her in a 3-versus-1 battle.
Initially, Reiko is very callous towards her child, planning to either experiment on it or eat it. She holds it poorly, and has it "trained" to stop crying when she commands. After giving birth and raising her child, she began developing and showing human emotions, such as laughter and love towards her son. She is eventually surprised by her own unconscious attachment to her child.
She sacrificed her own body to keep her son safe as the police shot a barrage of bullets at her. Before succumbing from her wounds, she revealed that she truly believed humans and parasites to be the same and that she enjoyed the time she had spent living as a "human".
Ryoko starts off as a substitute teacher in Satomi Murano's homeroom and math class, having managed to keep her original host's identity free of suspicion. She meets with Shinichi and displays no hostility towards him, instead convincing Migi to meet with her in the Herald Coffee Shop for the purpose of sharing information. In secret, she brings along Mr. A, who immediately identifies Shinichi and Migi as a threat. Although A and Migi posture menacingly at one another, Ryoko reins them in and speaks with Shinichi, revealing that she is pregnant with a human child. She concludes that parasites have no means of reproducing themselves. A displays no interest in the conversation and leaves midway through, while Ryoko threatens to kill all of a class if Shinichi causes her to be revealed.
Soon after, A is revealed to still consider the human-parasite duo a threat, and invades the school in broad daylight in an attempt to kill Shinichi. After his human host body is damaged by Shinichi's actions he tries to find Ryoko in hopes to transfer to her host. He tracks her to a room where she turns out to have set explosives, and she jumps out the window as the room explodes behind her with A still inside.
Later, Ryoko is invited to a staff conference and, because she is a pregnant single mother with no identity for the father, berated over the damage this would do to the school's reputation. Surprised that it is the pregnancy causing problems for her human life (likely having expected for Shinichi or a murder to cast suspicion on her instead), she then decides to quit being Ryoko Tamiya and leaves.
When Ryoko's mother learns from the school that her daughter was fired, she went straight back to Ryoko's home to see if she was alright after what happened. Upon meeting her, she then realizes something is very different about her from the daughter she knew. Deciding that this can no longer be her daughter, she attempts to call the police. Ryoko morphs and beheads her before she can.
During her pregnancy, Ryoko Tamiya changes her name to Reiko Tamura and meets up with Hideo Shimada. She convinces him to keep an eye on Shinichi as Hideo's host body is teenaged and capable of blending in.
She eventually gives birth and returns to the parasite meetings headed by Takeshi Hirokawa. After convincing the others to allow her to take responsibility and research Shinichi instead of killing him, she hires Shiro Kuramori to spy on him to see if anything changed.
However, once Shinichi and Migi manage to kill a parasite in a designated safehouse the group changes their minds and overrules Reiko. Because of her defending Shinichi, a lower parasite decides she is a threat and conspires with two others offscreen to kill her. The evening they meet, she ends up killing all three of them with no injury, but discovers her child was kidnapped by none other than Kuramori while she was fighting them. In the interval between this discovery and the meeting time he sets, she visits Shinichi's house while the occupants are away and goes through Shinichi's baby pictures. She manages to set up a meeting with Shinichi shortly after Kuramori's meeting time, crossing Satomi's path on the way out.
Reiko meets with Kuramori one last time and kills him after he threatens to throw her child off a balcony, both of them expressing surprise that she genuinely had maternal feelings. In a park nearby after she meets with Shinichi and informs him that Gotou's capability is far beyond his, as well as hinting towards Hirokawa's true nature, the police interrupt their meeting and brutally shoot her to death.
Her death causes Shinichi Izumi to start crying after a long time of inability to cry. The baby survives because of her decision not to fight back against the police and her son was adopted by another family.
Abilities & PowersAs a parasite, Reiko has the basic abilities to shapeshift her head and maximize the physical potential of the body she's controlling. She can harden her cells for offensive and defensive purposes. As well as mimicking someone else's face as seen in Episode 18 Where she mimicks Nobuko Izumi in order to gain Shinchi's trust. Her high intelligence allowed her to make use of unorthodox tactics when engaging enemies. She is one of the few parasites shown using tentacles to propel her around instead of walking or running, as well as the only singular parasite with more than one attack pattern. When targeted by three of her own kind, she tricked them into believing she had gone insane when she split her parasite in half. She was able to lure away Kusano, kill Maesawa by allowing the detached portion of herself to burrow and destroy him from within and then trick Kusano into killing Hikawa by burrowing into her and forcing her to attempt to kill Kusano. He kills her, allowing Reiko to sneak up on him and kill him when he unintentionally jams his ability to sense other parasites when he hacks Hikawa up.
In the Live Action film, she is able to split her parasite body in three, using them to pierce the heart of three of her own kind from behind, killing them without letting them notice. She can also extend her hair and wrap them around her son to protect him from the police's gun shots.
In addition, her intelligence and interest in the human mind allowed her to more effectively blend into society. She managed to keep her original host's identity before she decided to discard it, impressing Migi in the process.
- The original name Ryōko means "good, skilled" (良) (ryō) and "child" (子) (ko). Her new name Reiko means "tinkling, sound of jewels" (玲) (rei) and "child" (子) (ko).
- Reiko's original surname Tamiya means "rice field" (田) (ta) and "shrine, princess" (宮) (miya). In contrast, Tamura means "rice field" (田) (ta) and "village, town" (村) (mura).
- In the Tokyopop westernized release, she is renamed Tamara Rockford.