For some, it may also be a matter of temperament. Many of the ghosts are mischievous, some outright hostile. That makes them harder to train. Others, as you say, may be disturbed by the nature of these creatures.
[Y'know, the parts where they're the spirits of dead children or they eat souls or whatever. It's fine, par for the course where Geralt's from.]
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[Y'know, the parts where they're the spirits of dead children or they eat souls or whatever. It's fine, par for the course where Geralt's from.]