OK SO THIS IS ABOUT DISORDERS and you can skip this part but I really love talking about this because I have ADHD, Anxiety, and some kind of dyslexia, that's what my mom said. My dad also has bipolar disorder so I really like talking about this.
Yamaguchi has anxiety, that's obvious, so does Yachi.
Tsukishima has some sort of depression
Ushijima, Kageyama, and Kuroo all have autism.
Nishinoya, Hinata, and Bokuto have adhd
Kunimi & Suna have depression
Akaashi has insomnia, anxiety and ocd.
Oikawa has anxiety.
Kenma has a generalized social anxiety.
Ok so this one isn't really a disorder, but it fits here so Tendou is a HSP.
