To many, the body is a mysterious thing. Beyond the skin, the organs, and blood, not many understand what truly happens in there. Blood carries oxygen, sure. The stomach digests food. The brain thinks. Muscles…contract in some unknown manner. Anime tends to play with these unknowns, stretching science and biology to fit a quasi-fictional purpose. For some, that involves reanimation of the dead, an emergence of superhuman capabilities, or even just insane amounts of fighting. For Tokyo Ghoul, that stretch of biology manifests as a kagune.
Tokyo Ghoul takes place in an alternate Tokyo where two human-like populations exist: real humans and Ghouls. The former are just like you and I, while the latter possess insane strength, eat normal people, and can control blood-like appendages that extend from their back. These blood limbs are known as “kagune,” and appear at the Ghoul’s behest. They can be hardened and manipulated at will, creating a sort of biological weapon. As an example, the protagonist’s kagune appears as a a deadly, ever-changing, bloodied version of Doctor Octopus’ mechanical arms (seen in the featured image above).
Kagune are made up of Rc cells, which are mostly identical to normal blood cells. This name comes from the direct English translation of kagune, “red child,” effectively making these “red child cells.” It also pays homage to Rh antigens—the antigens responsible for “positive” and “negative” human blood types. Rc cells are stored in a sac-like organ in a Ghoul’s back. When triggered, the cells pierce out of the organ and through the skin, binding together into a cohesive structure.
This all sounds a little hokey, but certain details (beyond just the nod to Rh) are bound in reality. This sac-like organ acts almost as a secondary vascular system, although seems like Rc cells don’t carry oxygen like regular blood does. They likely play a role in a Ghoul’s extreme strength, speed, regeneration, and darkened eyes. It stands to reason that real-world blood logic may also apply to Rc cells.
Though Tokyo Ghoul says that kagune “pierce and erupt” through the Ghoul’s skin, it’s much more plausible that Ghouls have special capillaries designed solely for Rc cells. Humans capillaries often travel just below the skin; blood bursting out of these vessels cause pinpoint blemishes known as petechiae. As weird as it may seem, kagune could be an advanced, weaponized form of petechiae, brought about by Rc cells emerging through capillaries.
After emerging from the skin, Rc cells should remain liquid…right? Yet kagune are clearly semi-solid. Therein lies the next point of order: Rc cells undergo a “fixative stage” where they organize into a web of interconnected cells, slowly taking shape. That’s something human blood can do too: it’s essentially a blood clot! The difference here is that our blood forms platelet plugs and fibrin clots through complicated cascades of clotting factors. Rc cells sort of intelligently bind together. We also can’t control the form our blood takes—it clots as it pleases.
As far as I can tell, that’s sadly as far as the similarities go. So many questions are left unanswered. Do Ghouls flex their back muscles or Rc sac in specific ways to tweak the kagune’s shape and density? I don’t know. I’m a lab tech, not a physiology professor or manga/anime producer. Even so, it’s interesting to see the many times Tokyo Ghoul blurs biological lines beyond comprehension, and the times where it feels surprisingly grounded.
what's the dyl 