Tamaki Anzai


 * This article contains major plot spoilers from the manga that have not been revealed in the anime. Proceed at your own risk.

Tamaki Anzai (安斎 環) is the father of Yuuki Anzai whom he had with his human wife, Midori Anzai. He is a devil convicted of the mass murder of 15 people, and is said to be the most dangerous devil in written history. Although he received the death penalty, he is being held in isolation at the ONL facility for research purposes.

Pre-ONL
Tamaki fell in love with a human girl named Miho Kaneda and they were partnered for 10 years. They studied architecture in university together as they shared the same major. However, while they were deeply in love, she was gang-raped by 5 men while she was walking alone one night. Struck with depression, she took her own life. The 5 men were convicted and sentenced to 6 years in jail. When they got out after 5 years, Tamaki plotted to kill them all out of revenge. However, after he killed them, he had already lost control, and in a rampage, he killed 10 other innocent people including bystanders and the family members of the 5 men. Soon after, he was convicted of mass murder and sentenced to death.

Post-ONL
Drinking the blood of 15 people caused Tamaki to develop a strong dependence on blood. Since ONL was doing research on that subject, they secretly brought him in as a research subject, and he was able to avoid the death penalty. He was also decided to become a sperm donor for the 15th term of the Hybrid Project. Tamaki never got over the death of his love and even after the scientists and researchers there had stabilized his condition, he refused to talk to anyone and spent his days mourning in his cell. Even though he needed it, drinking blood brought back especially bad memories, like when saw Miho's corpse and visions back from when he killed the people in his rampage.

It wasn't until Midori Sako began having Dialogue Sessions with him that he started to open up. Tamaki can't talk, but he was able to use a whiteboard to write his responses to her and the two grew close over their sessions together. They even learned Japanese Sign Language together to make talking easier. Midori later gave him supplies for him to create a scale model house. Tamaki used those materials to create a dream house that he planned to make for his past lover. After finishing it, Tamaki was finally able to let go of his past that haunted him.

When the pairs of the Hybrid Plan had been decided, Midori told Tamaki that he had been paired with a woman named Ibuki Takeya. Tamaki didn't care who his partner was as he was just cooperating with ONL since he owed his life to the facility. But when Midori asked how he would feel if she would be the mother, it took him by surprise. The worry ended up giving him a fever and Midori came to see him in the hospital where she apologized for her blunt question and explained the project further. She informs him that it will be artificial insemination, which is a great relief to Tamaki who thought having sex would be impossible with a human. Tamaki then made it clear that he rather wanted Midori than anyone else to be the mother, and they then confessed their feelings to each other. With their love mutual, the Hybrid Plan was the perfect opportunity to have a child together. They got permission on one condition, they would use Midori's eggs and Tamaki's sperm, and get Ibuki's consent to become the surrogate for their child. This is because they couldn't afford to lose Midori; one of the most talented researchers, since being pregnant with children who have devil blood could cause health problems. Also because ONL could get a bad reputation for a serial killer and a researcher reproducing. Ibuki happily accepted their request and thus, their son Yuuki Anzai was born. ONL received full custody of Yuuki since he was a part of the Hybrid Project and had to monitored, so Tamaki and Midori never gained a legal parent-child relationship with him. Despite that, Tamaki always held a deep love for his son.

Since Midori's and Tamaki's love was mutual, despite the difficulties, they looked for a way to live together, in their own way, may it be Midori carrying a gun and tranquilizers with her, using handcuffs or not being alone together. Midori and Tamaki eventually got married.

Appearance
Tamaki is noted for being handsome and very similar to his son Yuuki in terms of appearance, except for his hair which is light-colored and wavy since he is one-quarter English.

Due to his heavy dependence on blood, Tamaki is perpetually stuck in his transformed state. His nails on his fingers and toes are long and claw-like. His teeth protrude greatly from his mouth and impede his speech to the point that he rarely talks and if he does, it is done quietly and in small words. The only thing that remains normal is his eyes, although these can turn red under the right circumstances.

It also seems that Tamaki has scarred himself with his claws. The scars can be seen on his cheeks and his left shoulder. There is also a large scar on his neck.

He is often seen wearing nail protectors on his fingers and toes as well as handcuffs and a mask over his mouth.

Midori Anzai
Midori is Tamaki's wife and they have been married for many years. Midori says that they are as "lovey-dovey" now as they were 20 years ago. When they first met, Tamaki and Midori developed a very close bond. She was the only one who was able to communicate with him and she was also the one who helped him ease his depression and accept his former lover's death, resulting in him becoming a happier and more communicative person. Tamaki was very grateful for this and came to care for her deeply, worrying about her whenever something would happen and he would also comfort her when she felt down. After being informed about the Hybrid Plan, Tamaki confessed to Midori by saying that he would rather have her than anyone else to be the mother of his child in the project. While comfortable in her presence, he was also seen to be very flustered and embarrassed whenever she got too close to him.

Although he likes her, he was surprised that she liked him as he was sure that she could have anyone she wanted, but Midori reassures him that he is the only one she wants to be with. After having a child together, despite not having custody of their son, their relationship became even stronger despite the major difficulties; they married and although they are away from each other for sometimes extended periods of time, they spend as much time with each other as possible and they regularly report their daily schedules to each other. Whenever something happens, may it be significant or not, they always hurry to break the news to one another. They are a very loving couple and Tamaki is protective of her, as he wants her to be safe when he isn't there with her. He loves her deeply and hopes that someday, they will be able to be more physically intimate with each other. Since he is stuck in his cell and his transformed state, Tamaki also wishes he will be able to hug his beloved wife someday above all.

Yuuki Anzai
Although Tamaki has been absent for most of Yuuki's life, he loves and cares for his son dearly. He is ashamed of himself due to his past actions which is why he absolutely doesn't want Yuuki to find about it. So when Kirio Kikuhara told Yuuki about Tamaki killing 15 people, Tamaki was seen to be absolutely devastated and enraged. He regrets having traumatized Yuuki when he was a child due Kikuhara's actions. Tamaki wishes to have a proper reunion with Yuuki someday and hug him as well.

Trivia

 * He is one-quarter English and has several relatives living in the UK, including his grandmother.