Yūichirō's father

Yūichirō's father (優一郎の父) and Yūichirō's mother (優一郎の母) were the parents of Yūichirō Amane, who is later goes by the name Yūichirō Hyakuya. The step-mother appears in Seraph of the End: Guren Ichinose: Catastrophe at Sixteen. They also appear as characters in Yūichirō's nightmares in Seraph of the End: Vampire Reign.

Although Mrs. Amane was confirmed to be Yūichirō's step-mother, it is unconfirmed if Mr. Amane was his real father.

Yūichirō's father
An adult man with dark blue hair with bangs only on his left side, and light green eyes. He wore a sweater over a collared shirt.

Yūichirō's mother
A pretty Japanese woman with long dark green hair, who appears to be about twenty-five years old. When she screams about killing Yu, her face is twisted and her hair disheveled.

In the manga, she appears to be wearing a sweater.

Yūichirō's father
He curses Yu as demon spawn and condemns him for ever being born. He believes that killing Yu and the Seraph of the End is for the greater good. In Yu's nightmare, he comes at Yu with a knife.

Yūichirō's mother
She absolutely hates her step-son Yūichirō and believes that he is a demon that should die. She pours gasoline on herself and attempts to light herself on fire while in front of news crews and firefighters, who stop her attempt. She does not appear to be mentally stable.

In the manga, she lets her husband do the screaming.

Events of 2012
The Amanes' apartment goes up in flames, and firefighters struggle to get it under control while newscasts swarm the area. The six o'clock news broadcasts the scene. Mrs. Amane runs forward and begins screaming that Yu is inside.

A firefighter struggles against her and asks for help, stating she has "some kind of crazy strength." She punches the firefighter in the jaw. They continue struggling as she screams.

She pours a plastic bottle of gasoline onto her head with her left hand and begins flicking a lighter with her right hand. The spark does not catch.

One of the firefighters punches her in the face, knocking her to the ground. Several others tackle and hold her there as she continues screaming about killing Yu.

Saitō appears wearing a hooded sweatshirt and makes the broadcast go dark.

When driving Yu to the orphanage, Saitō reveals that Mrs. Amane is his step-mother, but he does not tell Yūichirō.

Post-Shinjuku Arc
Yu faces Asuramaru in a battle for control within his mind. The illusion shows Yu as a child in his home with his father and the step-mother before the apocalypse. The room is a mess with an overturned table and bottles, papers, and pens scattered on the floor.

His step-mother kneels on the ground in the kitchen with her back to him. His father curses him, calling him demon spawn. Mr. Amane says he must kill the Seraph of the End as soon as possible or else the world will be ruined. Yu realizes his father is holding a large knife, and he tries to plead with him, saying he will be a good kid. His dad says that killing Yu is the right thing to do.

Yu screams that he is not the devil, and his dad chases him into an oversized apartment hallway, where he encounters Mika and Akane once again.

Mika blames Yu, stating he became a vampire because Yu ran away. Akane wishes Yu never came to the orphanage.

Mr. Amane appears in the doorway and tells him to die. He stabs Yu through his back and left chest.

Yu fights the illusion, stating he will not go berserk over something like that.

Shibuya Arc
With Yu's grief over what has befallen Mika, Yu remembers his parents saying that he was devil spawn and did not deserve to live.

Book 3
"Don’t put out the fire! He’s a demon! That boy is a demon! I have to kill him! I have to kill him today! Aiiieeeeeee!!"

- Yūichirō's mother about Yūichirō in the fire.

"He’s a demon! I have to kill him! I have to kill him!!"

- Yūichirō's mother about Yūichirō.

Seraph of the End: Vampire Reign
"Demon. Yu, you're... demon spawn! Why were you even born? We have to kill the Seraph of the End... We have to kill it now!! If we don't, the whole world will be destroyed..."

- Asuramaru's illusion of Yūichirō's father.

"This is for the greater good. Killing you... is the right thing to do!"

- Asuramaru's illusion of Yūichirō's father speaking to Yu.

"Die. This is the end for you... demon spawn."

- Asuramaru's illusion of Yūichirō's father speaking to Yu.