A Lonely Death — Gillian Larkin

A short murder mystery with ghosts.

Derek Quill is an elderly gent who can see the ghosts of murdered people. With the help of his ghostly friend, Pearl, he finds out who killed them.

In his first investigation, Derek meets the ghost of Eric Malone. Derek knows Eric from his schooldays. Eric bullied Derek mercilessly back then and now he's asking for Derek's help. Derek soon discovers that Eric never changed his bullying ways and there is more than one person who could be a suspect.