After they called the bureau investigators and explained the situation to them, they were told that they could go now.

As they walked toward the subway station, Yukina asked, "Do you want to go back to the office once, or...?"

"No, let's just go straight to your house," Amon said.

"Okay," Yukina said. After that, neither of them talked. The two silently walked to the subway station, got on the train, got off, and walked to Yukina's house. They went up the stairs of her apartment and to her room, with Yukina leading the way. Yukina opened the door and went inside, and Amon followed her. They put their Quinque cases down by the entrance and went through the kitchen and into Yukina's bedroom, which was rather small but very clean and tidy.

"It should be in here," Yukina said, pulling out a cardboard box from her closet. She opened the lids and searched through it. It was neatly organized, and she quickly found the letter, which was sorted among other papers in the box. Yukina held the envelope in her hands, titled "To 15-year-old Yukina," and stared at it for a while.

"...Is that it?" Amon spoke.

"Yes," said Yukina. "Please give me a second so I can read it." She opened the envelope, took out two sheets of paper folded in half, and opened and read the letters silently to herself.

Dear Yukina,

Happy 15th Birthday! I can't believe you're already 15 years old. Well, when I'm writing this, you're still 12, but...there's something that I decided to tell you when you turn 15, but it seems like I won't live for very long. So I'll leave you this letter, and hopefully, you'll read it when you're 15.

First of all, I want to tell you about your dad. Your dad and I met when we were in college. We were both in gardening club, and we were shy at first because we were freshmen. But we got close as we talked about flowers, and we started going out when we were sophomores.

We continued going out even after we graduated. I was waiting for him to propose to me, but he didn't. So one year, on Christmas, I asked him if he would marry me. He started to say something, but he hesitated and started to cry quietly. I remember being surprised because it was the first time I saw a grown man cry. After a while, he said he loved me and explained to me why he couldn't say yes, and why he never proposed to me.

Your dad's dad, or your grandfather, was a ghoul. And your dad, half-ghoul and half-human, had to eat what ghouls eat, and he's suffered from this all his life.

I've actually never hated ghouls. I just thought it's scary that they eat humans, but at the same time, I felt sorry for them because they were born that way. It wasn't their choice to be born as a ghoul, but because they were, they had to eat humans and constantly worry about the ghoul investigators killing them. So when your dad told me he was a half-ghoul, I was surprised, but I didn't reject him. I said, "Oh, so ghouls aren't bad people like they always say on the news," and I hugged him and told him that I love him regardless of whether he's a human or not.

But since my life might be put in danger if we marry, your dad suggested not to officially marry. If the CCG finds out that your dad is a ghoul, then I might be punished too, you know. So we never married. Your last name, Teshigawara, is my last name, and your dad's is "Mitsuse."

Unfortunately, you probably don't remember your dad because when you were only one year old, someone found him eating and reported to the CCG, and he was killed by investigators. I was prepared that this might happen someday, but I couldn't help hating humans for killing ghouls without thinking about their character or family. But then, I couldn't blame the investigators, since ghouls are indeed predators to humans, though not merely predators (if they were, I wouldn't be married to your dad). I blamed the world for being so cruel, making ghouls the ones who eat humans, and humans the ones who get eaten.

And so I suppressed my anger toward the CCG by telling myself that it's not their fault but the way the world is made up. This couldn't be helped. I didn't talk to you about your dad much for the past 11 years because I feared that I might remember this feeling of anger... I didn't want you to see me with a face full of hatred.

You've been able to eat and live like a human ever since you were born, but after your dad died, I started thinking, "What should I do if you start showing characteristics of a ghoul?" I can't give you a good advice because I don't know much about ghouls. So when you were two years old, I wrote a letter to an old friend of his. His friend responded that we can come by any time and that he will gladly talk with us. I felt relieved, and I decided to go to him for help if I ever need it.

I wonder how you are right now as a fifteen-year-old? I hope you're still able to live normally, but even if you start to see changes in your body, don't worry. Go to a cafe in the 20th ward called "Anteiku," and talk to the manager there. Tell him that you're Mitsuse's daughter. He has a great understanding of ghouls, so ask him anything.

This whole letter might be absurd and unbelievable, and I'm sorry if this letter makes you confused and stressed out...but I just want to tell you one thing. Going back to when I was pregnant, I didn't go to the hospital because I feared they might find out that you're a part-ghoul. So I gave birth to you at home. Since I didn't know if you were going to be a boy or a girl until you were born, your dad and I thought of a girl name and a boy name. We decided on Yukina if it was a girl - "Yuki" meaning "happy" and taking a part of my name,"na" - and Yuuki if it was a boy - "Yuu" meaning "exist" and "ki" meaning "rare." You were a girl so we named you Yukina, but I hope our wish will come true: that you will live happily, knowing that you can exist and that we're glad that you exist, even if you are a rare type of person.

This is my opinion, but I think ghouls have the right to live just like humans do. I know this sounds ironic since ghouls eat humans and humans kill ghouls, but we should all have the right to live from the moment we are born into this world. So even if you start seeing aspects of a ghoul in you as you grow older, please know that you have the right to live. You're our one and only precious daughter, and we want you to live a happy life.

Love,

Mom

After reading the letter, Yukina buried her face into the letters and let out a big sigh.

"...My mom...she became ill when I was 11. It says here that there was something she wanted to tell me when I turn 15, but since she thought she might not live until then, she wrote this letter when I was 12. It makes sense, since my mom was serious and kind of a worrywart," Yukina said, her voice trembling.

Amon watched her quietly and waited for her to continue. After a moment of silence, Yukina lifted her face and looked at Amon with a distressed expression. "According to the letter, my grandfather on my dad's side is a ghoul," she said with a frown.

"What?!" Amon exclaimed, unable to hide his surprise. "Even half-ghouls are unusual, but a quarter...?"

"Yes, I've never heard of a quarter-ghoul," Yukina said, folding the letters back in half. "I think I was able to live as a human because my body was so close to a human's. But I guess something triggered my ghoul part to start functioning."

"So I guess that was the trigger... I'm sorry, Yukina," Amon said, looking ashamed.

"No, I'm responsible for my own actions. You don't have to apologize," Yukina said. She opened the letters once more, and after glancing through them once more, she folded them again and put them back in the envelope. "But I'm not sure if I want to keep working as an investigator, so could you please give me some time to think by myself?"

"Oh, yeah, sure. Well then, I'll be going now," said Amon.

"Okay, see you tomorrow...I mean, on Monday."

Yukina put the envelope with the letters in it on her desk, and she and Amon went to the door. As Amon put on his shoes, Yukina smiled wryly and said, "I'm sorry for betraying you, Amon-san."

Amon looked at Yukina and asked, "Huh? What do you mean?"

Yukina looked back at him, surprised. "Um, well, because I insisted that I was a human, and you believed me, but...I was actually part-ghoul."

"Oh, I see. But like you told me earlier that I don't have to apologize, you don't have to either."

"Really...?"

"Yes. I mean, there are could've's and should've's. Like, if you read the letter two years ago, you could have taken time to think about whether you actually want to be an investigator or not. But it's not like you were lying to me on purpose, so I don't feel betrayed."

"...Thank you, Amon-san. Good night," Yukina said, bowing.

"It's your future, so think about it carefully, all right?" Amon said, picking up his Quinque case. "Good night," he said, and with that, he left Yukina's apartment room.

As Amon walked down the stairs of the apartment, he thought, Ghouls are guilty only because they eat humans... Even if Yukina is a quarter ghoul, since she's never eaten humans, she isn't guilty. Is that right...Mado-san?

But no matter how much he thought, he couldn't find an answer to his question.

Meanwhile, Yukina stood in front of the door, listening to Amon's footsteps become quieter and quieter. After it became quiet, she looked at her watch.

"7 o'clock... There's still time," Yukina said. She went to her room and changed into a light-yellow T-shirt, a pink jacket, and blue jeans. She left the apartment with nothing except her wallet and cellphone, and she walked in the darkness, heading to Anteiku.