Shirion may have been a human once. That time is long past. Now, it is an ever-shifting being, its form lost to time.
Brendan stared at the creature in the pale moonlight, transfixed by the silvery petals that glistened beneath that perfect purity. It was not until his final breath that he gathered his wits enough to scream after the thing had descended on him, all muscle and thorns and hard, barklike skin. It was too impossible, even the crimson blossoms that shone in the light of the moon.
These small, luminescent creatures are a distant relative of the willowisp, little bits of orangish light that are attracted by the flames of a fire. When enough of them have gathered around a fire, the fire appears to take on a fuzzy indistinctness.
On a world made entirely of molten rock, there is still life.
A vicious murder happens in a town that the party happens to pop in at. Under heavy suspicion as they are strangers, the party is forced to discover the perpetrator or have their reputations blackened, especially as more and more murders occur in the town, and mysteriously stop and restart when the party leaves to go kill off that evil necromancer who kidnapped the princess.
The only problem is that a demon, possessing one of the party, is the perpetrator. And the demon makes no signs that its living in the PC's head.
In fact, for all the party knows (except for the possessed person's), their companion is an evil murderer.
Do they try and execute their friend as he's a vicious murderer, and no evidence points to demonic posession? Or do they flee town with him, trusting him, and have their reputations destroyed?