The Ancient Magus' Bride: Those Awaiting a Star(2016)

Mahoutsukai no Yome: Hoshi Matsu Hito

The three-part OVA series will chronicle a story taking place before Chise meets the Magus.
Chise Hatori has lived a life full of neglect and abuse, devoid of anything resembling love. Far from the warmth of family, she has had her share of troubles and pitfalls. Just when all hope seems lost, a fateful encounter awaits her. When a man with the head of a beast, wielding strange powers, obtains her through a slave auction, Chise's life will never be the same again.

(Source: Seven Seas Entertainment)