Can multiple ghosts use Malevolence on one creature?

Question

Ghosts have the ability Malevolence that allows them to possess a creature.

This ability is similar to a magic jar spell (caster level 10th or the ghost’s Hit Dice, whichever is higher), except that it does not require a receptacle ... If the save fails, the ghost vanishes into the target’s body.

However, it's unclear what happens when a ghost is possessing a being, but another ghost wants in on the fun. Magic jar specifies what happens to the soul currently occupying the body - it goes into the jar. But Malevolence does not use a receptacle, nor does it specify what happens to the original soul.

So what happens when a ghost successfully uses Malevolence on a creature already possessed by another ghost?

Answer 1

As written, it looks like the last ghost in "wins". Each ghost "merges with" his victim when malevolence succeeds, and presumably the merged creature stays on the prime material. At that point, the new merged creature is a fair target for a new ghost's malevolence.

Magic Jar is cleaner, as it only allows one soul per body. Malevolence gets rid of that restriction by eliminating the focus (which is where the extra soul would otherwise go to). I don't think that failing to shunt the original soul to some new location changes any other effects though (so the possessor still gains control, even if the original soul isn't ejected).