Vaelle was part of an unknown cultist group.
She was ordered to retrieve The Stone of Golorr from a tomb in the City of the Dead together with a few other cult members.
Upon retrieving the stone, she and three others were stabbed in the back by the remaining cultists. Apparently they were ordered to do some by the higher-ups in the cult.
Vaelle managed to survive the attack long enough for The Trollskull Crushers to arrive and save her. Together they tracked down the backstabbers to an old windmill.
During their confrontation with the two cultists, the Trollskull Crushers end up destroying half the windmill, trapping the cultists underneath a pile of rubble.
While the crushers quickly take off in chase of the Stone of Golorr, Vaelle remains at the windmill to take revenge on her two ex-comrades by slitting their throats while they were stuck in the rubble.