Spawns enemies in Yahar'gul, Unseen Village and Chalice Dungeons. If you see enemies with a red glow charging towards you there's a chime maiden nearby. She should always be your primary target, killing the spawned creatures aren't always a bad thing though since it takes a couple of seconds for her to summon another.
Sometimes the red glowing enemies dies at the same time as the Maiden, sometimes not. Testing needed what is the deciding factor.
Can two hand a dagger and attack the player, slow wind-up and easy to avoid. If you're not chased by 8 respawning spiders that is.
Can do an AOE by ringing her bell, a red glow fills the area that is affected.
Rush in and kill the her first. Always prioritize her.