Ansen Dibell’s 1978 Pursuit of the Screamer is the first volume in her Strange and Fantastic History of the King of Kantmorie planetary adventure series. It is also the very first Dibell I’ve ever read.
Jannus encounters Lur, a Screamer, so named because they telepathically broadcast confusion and fear. The empathic Valde, a guild of female warriors and guards, kill Screamers whenever discovered. But telepathically deaf Jannus sees only a small, frail fellow human. Rather than hand the Screamer to the Valde to be killed, Jannus helps the Screamer escape. It’s a decision that will shape the boy’s life.