Murin are small fox-like creatures, long bodied and short limbed. They are about 2'6" to 4' long, excluding their tufted, slightly prehensile tail. They can be almost any color, but most often are shades of silver, black and brown.

They are most often thought of as merely "pets" by both minena and kaasht, but this is just a ruse. Murin are in fact reincarnated kaasht or minena, who are given the choice upon their deaths by Kami, the Spirit Elemental, to return to Tryne and help the living. A murin will choose a kaasht or minena of any age to bond with, to act as conscience, counselor, guide and companion. Because they are physical manifestations of kaasht and minena souls, murin do not reproduce, and they are genderless. They do not grow, and they can appear whatever age they choose. They can be injured and heal, but they cannot really die, as they are already dead - but they aren't exactly immortal either. If a murin were to be physically "killed" it would merely be sent to the Spirit Plane, and then after a time be able to return, though they could not return to their bond. The "death" of a murin doesn't automatically kill their charge or cause them to be suicidal - it would be a loss to mourn, but nothing more.

Most murin were Elders in life, as they are most likely to be able to impart a full life's wisdom to their charge. But kits as young as 50 and minlings as young as 35 are occasionally given the chance to become murin. Though they do not have magic like kaasht, nor immunity like minena, all murin have certain psionic powers. They do not normally walk, but levitate, floating in midair. They can teleport, "winking" here and there via the Spirit Plane, and can cover large distances if they choose. If necessary, they can make themselves visible only to their charges, or to whoever they choose. They cannot speak audibly, thought they can "speak" to their bond with telepathy, usually simple pictures and emotions, but they are capable of "speaking" in words. It is generally thought that murin only speak to their bonded, and though they can speak to others, it is rare. It is also possible for a murin to take more than one kaasht or minena as a bond, but almost never more than two. Two is plenty. Trying to keep track of three minds would get a little hard, and groups of two are easier to keep together than groups of three, and with three charges, one would end up feeling left out at one point or another. Murin do not normally grow weary, with a direct link to the Spirit Plane keeping them constantly refreshed, but a murin will grow fatigued with too many bonds to look after. Even a murin with two bonds is very rare, as often their charges would become jealous.

Though murin do remember their previous lives, they are not permitted - indeed, they are unable - to tell others the details of their previous life.