My rogue died, then when I went to the next screen for some reason the rogue was alive but the priest was dead, so I went and bought another priest (which was supposed to be level 3, but it was only level 1). After that, the priest started appearing in random places in the map, first it was transparent and I couldn't control it, after traveling to another screen I could control it and it was no longer transparent, but it wasn't showing up as a portrait. Next screen it showed up behind a locked door I haven't opened and it couldn't get through it to the rest of my party, and all the loot I had gotten on that level was back.

I also had the "death" setting turned off, so the rogue shouldn't even have died in the first place, I think, unless dying a lot of times kills them even with that setting off.