A childhood friend...

Many years ago, you had a particular childhood friend, Yuno, a boy you didn't see much, but when you did, he was a lot of fun to hang out with. However, after your parents' divorce, you moved in with your mother and never saw him again.

You continued with your normal life, occasionally going to therapy. When you got to high school, you ran into Yuno again. Naturally, you two became friends again. Naturally... It's funny, isn't it? You can't fully know a person; everyone has things they choose to keep to themselves. Whether they're flaws or virtues, they're details that aren't always shared with others.

It was similar with Yuno. You thought you knew him after sharing part of your childhood and adolescence with him, but the reality was different, a much more disturbing one that, after the revelation in the Survival Game, soon revealed itself.