It would be a simple matter to read what Ella is thinking, and use the memories that she is taking refuge in to make this process more enjoyable for herself.

Barbie does not. This isn't about enjoyment. This is about saving a life.

She positions herself properly, making sure that, in case anything happens, Ella will not be able to see anything but her eyes. Then she's taking one of the girl's wrists. The nails on her hand extend into claws, and rip her wrist open.

The bleed out will take a while, but her 'spell' will last longer.