Shiro

In the past, Sorae Igarashi, not wanting to use her own son in her and Hagire Rinichirō's experiments, went on to adopt a female albino child to use as a substitute.

Before the birth of the Wretched Egg, Ganta and Shiro played quite often, sharing a common admiration of Aceman. They first met when Ganta saw her sitting by a tree and commented on her white hair. Shiro became embarrassed about her hair, but Ganta told her he liked it, making her feel better and they started playing, eventually becoming good friends.

She and Ganta normally got along quite well, but once, when Shiro was in grave pain because of the constant injections, they once bickered so violently that Shiro broke his Aceman action figure and Ganta took his toys and ran away from her in tears. Soon after, he came face-to-face with a rabid, vile dog, one of the other test subjects that escaped from the lab. Ganta dropped to his knees in fear and called for Aceman to save him. Suddenly, Shiro jumped down from a window and landed on the dog, knocking it out and saving Ganta. After this, Shiro vowed to become Ganta's "Aceman" whenever he was in trouble.

Because of Hagire and Sorae's experiments, her body would often deteriorate, and needed to be sewn back together. Her arm fell off once while she and Ganta were playing hide-and-seek. She has also been seen with her leg being sewn back on. She was used in excruciatingly painful nanomachine experiments, causing her to create a separate personality known as the Wretched Egg to cope with the pain.

The Wretched Egg was the cause of the Great Tokyo Earthquake. It was revealed in Chapter 55 that this wasn't an accident; it was actually Wretched Egg attempting to use her powers to such a degree that she could destroy her body faster than it could regenerate, as an attempt to commit suicide. Sorae created the Mother Goose System afterward to prevent her from trying it again, but gave her a small measure of hope by showing her the red crystal, and stating that she could still 'get her wish.' The moment she found out Ganta's class would be taking a field trip to Deadman Wonderland and saw his name on the list, she stole the red crystal, and broke out of the prison entirely to infect him with it.

Hagire built a room for Shiro in Deadman Wonderland, supplying her with all the candy she could ever eat.

Shiro is a young albino girl. She has snow-white hair, pale skin and red eyes; even her eyebrows and eyelashes are white. Her hair is very long and reaches down to her knees. She dresses in a peach, skintight bodysuit (white in the anime), decorated with red circles and stripes and with her toes and heels sticking out. She also wears big brown mittens and a white neck warmer, though has been seen wearing black mittens with a black neck warmer and also black winter boots. Ganta has mentioned that she looks like Mimi.

When the Wretched Egg takes over her body and Shiro becomes trapped in her own mind, she is seen wearing a white nightgown.

The Wretched Eggs appearance is, for the most part, that of Shiro's, however, she always has a hooded and lazy look to her eyes and a wicked bloodthirsty smile on her face.

She used to wear a red, worn-out cape with a mask that covered her nose and eyes, without any holes. As the Red Man, she also wore a heavy suit of armor that defends her body, legs and arms. This outfit actually makes her look like Aceman, a superhero Shiro looked up to and what she calls the Wretched Egg.

The Wretched Egg ends up changing her look. Now, she has a light purple and lavender lace bodysuit with long sleeves that are torn at the ends. She also wears a metal collar with a small chain attached to it.