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Name Jaw
Other Names, etc. Parasite
Japanese パラサイト (Parasite)
ジョー (Jaw)
Rōmaji Parasaito
Gender Male
Status Alive
Species Parasite
Eye Blue
Partner(s) Mamoru Uda
Series statistics
Anime debut Episode 7
Manga debut Chapter 14
Seiyuu Ayumu Murase
English Voice Greg Ayres
Image Gallery

Jaw (ジョー, lit. ) is the parasite that infected Mamoru Uda's neck and jaw. At first, Uda simply calls him the English loanword "Parasite" (パラサイト, Parasaito), and later gives him the name "Jaw" once "Parasite" becomes a popular term for the monsters in general.


Jaw partially emerged

Jaw has blue eyes and sharp teeth. Due to being a parasite, his appearance is malleable. Most of the time he is camouflaged as Uda's lower face and upper chest.

The way that he emerges from his host's neck also gives him the resemblance of a goiter.


Like other parasites, he can think logically and take the right action when the time needs it, shown when he changed Uda's vital organs, so he can eventually survive from Shinichi's parasite mother's attacks. Similarly, he puts little importance on names and gives little attention to being renamed from Parasite to Jaw.

However, unlike other parasites, he is often seen smiling and appearing generally gregarious. He is also readily willing to work with Shinichi and Migi because of their similar situations. He has stated he prefers to use all of his body when speaking, even though it inconveniences Uda by not allowing him to speak. Despite his emoting, he has little respect for Uda's sensitivity and tendency to cry, stating that it is something unique to humans that he doesn't understand.

Jaw learned the language by watching movies with his host (who usually cried during the films). It's noted on multiple occasions that he can be rude, something that seems to increase as the series progresses as he often insults or denigrates his host. His tendency to smile and emote may also be a mimicry of the shows they watch.


Jaw breathing for Uda

Jaw was first seen in his more worm-like state, falling from a tree and attacking Uda. Taking him by surprise as he entered his body through his lower neck, this caused Uda to fall off a cliff and into the water below. Confused as to why his host's body was failing, Jaw had to quickly abandon his goal to take over the brain and transformed his chest and lower face instead, stretching out Uda's mouth in order to breathe oxygen. Doing this meant Jaw failed to take over the brain, but managed to gain control over Uda's jaw and neck.


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Jaw is first seen revealing himself to Shinichi and Migi, showing that they're in the same predicament. At the time he was named Parasite by Uda. The two of them make contact with the parasite that had taken over Shinichi's mother and inform Shinichi that they're going to a different location.

Now in the woods, Uda and Parasite try to come up with a plan. Due to Uda being overweight, he quickly becomes tired and goes with the plan of standing their ground. Bringing the fight to a cliff, the parasite catches up with them and begins combat. Though holding their own in the beginning, the awkward position in which Parasite is located in his body soon left them at a disadvantage. The parasite then proceeds to stab Uda in the chest, causing him to fall off the cliff.

As Shinichi is taken aback during his fight with his mother, Uda and Parasite decapitate the parasite. As Uda climbs back up the cliff, Parasite reveals that by shifting the position of Uda's internal organs, he managed to prevent lethal damage.

After the hair pulling trend becomes popular, Uda is seen having his hair pulled by his employer, making sure he wasn't a parasite. After his boss leaves, Parasite comes out and warns Uda that he needs to be more cautious than ever.

Later, after Kuramori is discovered by Shinichi and Migi to be stalking them, they contact Uda to help them capture and talk to him. Uda tells them that due to the increasing presence of parasite news in the media they decided to change Parasite's name to Jaw.

Abilities & Powers

Being a parasite, Hideo can shapeshift from the head up and harden his cells for offensive or defensive purposes, as well as to detect other parasite signals and automatically emit his own. He can also maximize the host body's physical potential and disregard pain.

He's intelligent enough to recognize an enemy parasite's attacking patterns and due to his position on Uda's body. He's also able to shift Uda's organs around when they're being attacked, which allows Uda's body to be pierced and survive instead of being stabbed through a vital organ. Jaw can also elongate Uda's mouth and prevent him from drowning, acting similar to a snorkel.

Unlike other parasites, Jaw has no hair and easily avoids detection from the hair-plucking method.

During Kumamori's abduction plans, he's shown mimicking Kumamori's face like Migi and is capable of drastically changing Uda's lower jaw to look completely different from his actual face.


Like Migi, he relies on nourishment from Uda's bloodstream and would quickly die if detached. Because of the odd position in which Jaw is located, it puts him at a disadvantage in combat. It causes Uda to be dragged forwards and experience mild pain when Jaw stretches out or changes form and forces Uda to breathe only through his nose which causes difficulty breathing when in an intense battle.

Because they share the mouth area, only one of them can fully control it at a time, though Jaw can cede half of his control to allow Uda to talk at the same time as him.


  • In Tokyopop publication, Jaw is referred to as "Jaws" in reference to the American thriller film, Jaws.
  • Due to Japanese grammar and sentence structure, Jaw's gender is likely never addressed in the original untranslated work. However, his personal pronoun, "Ore", tends to be used by males.