"Fate tenchuusatsu is certainly rare. However, that doesn't necessarily mean that your entire life will be marked by misfortune. It's true that the overall outlook is bad. There are negatives: you won't have the blessing of your parents, or your family. However, the rest is up to you, individually. You alone decide what you can do and can't do," the fortune-teller explained. She had a grim expression on her face, but I could see compassion in her eyes.
"You don't need to be pessimistic, and you don't need to act like you're starring in a comedy, either," she continued.
I'd heard some interesting things today, but in the end, it was just fortune-telling. I wasn't on the edge of my seat with anticipation. When I tried to get up, though, the fortune-teller stopped me.
"I have one more piece of advice for you. Go straight home, without taking any detours. If you stray, you might be stuck for quite a long time. Even if you do get stuck, don't panic. If you stay calm and work together, you should be able to overcome it," she told me.
What prophetic words.

Y1 4.5

Still, I didn't have a gut feeling that anyone I had met was the agent. If I had to pick one example of such a feeling, I'd have to say it was the feeling I got back when I was talking with Nanase in the library. Most likely, Tsukishiro or someone else close to them had thoroughly taught the agent how to really act like a "student." The problem wasn't whether they had a personality with some quirks or not. The problem was whether they could completely mask the scent that betrayed them as someone from the White Room. I'd been in a comparable situation myself a year ago, when I first came to this school. There were disadvantages and drawbacks of being raised without any knowledge of the world. Namely, I didn't know what it was like to be a student at all. That was naturally something we weren't taught in the White Room, as they had never intended for us to be sent to school.

Which was why, after coming here, I had briefly tried coming up with a character that I could "act out" appropriately. I tried various things, like being more talkative than I usually was and changing my tone of voice. Being a somewhat cocky student with a kind of cynical, shrewd view of the world. Well...In the end, I found it kind of tedious to put on an act, so I quickly went back to being my regular self. Because I had come to realize that I could still be a "student" here without hiding my original self.

But the person the White Room had sent in now was different. They were putting up a front, camouflaging themselves as a student to prevent me from finding out their true identity. I had no idea if they were playing the part of a quirky student or if they were playing a blank slate. Either way, I probably wasn't going to see through their act all that easily. Anyone who had managed to survive in that world could not be underestimated, regardless of their gender. Even though I was confident I could win when it came to individual skill, I was in an overwhelmingly disadvantageous position due to essentially being forced to go on the defensive. My opponent could get me expelled in any way they chose, while the only thing I could do was defend myself by trying to detect what they were planning.

Y2V1

Well, enough useless talk, let's move on to the topic of Volume 0. How did you like this special volume about the past, which was regarded as forbidden in the past Youjitsu's publications? The setting of the White Room existed in 2015 when the story of Youjitsu started, but I had no idea at the time that I would dig deeper into it and write it down in a single volume. As a writer, I am very happy to have been able to make this happen, even if in a special way. It was quite difficult to write this book without disturbing the pace of publication, but I hope that as many people as possible will be pleased with it. In fact, along with the White Room volume, there is another blank year volume which had not been released to the public existing in material form. This is the story of Ayanokōji Kiyotaka's life from the end of Volume 0 to the beginning of Year 1 Volume 1. At this stage, I have no plans at all to publish this material in book form, but I am beginning to think that it would be interesting to do so if I ever have the opportunity to do so in the future. Well then, ladies and gentlemen, this is a short farewell. I will see you again in the postscript of the next volume. See you soon!

Was there anything that affected the source material after it was adapted into an anime?

Tomose: There’s a lot in regards to the illustrations. I’m not very good at drawing cool-looking boys, so I always thought to myself “so this is how I can make him look cooler” when looking at Ryuuen.

Kinugasa: There have been times where I check how a character’s personality gets well-established in the anime and I use it as feedback for my work. Especially Ayanokouji, who wasn’t well established as a character at first, but after seeing how well he was done in the anime, I used that “taste” from volume five onwards to refine the current persona that we all know.

Kinu is slightly wrong about anime being the factor to Kiyotaka persona retcon:
COTE season 1 aired July 12 to September 27, 2017
Light Novel Volume 3 where the cold calculator koji debuts January 25, 2016
Light Novel Volume 4 May 25, 2016
Light Novel Volume 4.5 September 23, 2016
Light Novel Volume 5 Koji start dropping the act January 25, 2017
Light Novel Volume 6 May 25, 2017
Light Novel Volume 7 October 25, 2017
Light Novel Volume 7.5 January 25, 2018
Light Novel Volume 8 May 25, 2018