Monnay

Monnay was a human living on a colony planet of Earth where artificial trees were used to provide sustenance for the colonists. However, over time, their purpose was forgotten and the colonists began to sacrifice young women to the trees in the belief that it would keep them safe, not knowing that they were actually stasis chambers.

As a result of this belief, Monnay was sacrificed against her wishes by her mother, the forest elder, one year's Bridal Day. A year later, the Thirteenth Doctor and Yasmin Khan discovered her but were unable to recover her like the rest of the sacrificed brides due to her arm breaching the tree when she was frozen in it. (COMIC: The Forest Bride)