The Centaur’s Sacrifice by Lorelei M. Hart

Marcus is looking to keep magics of old where they belong… buried deep in the past.

Marcus’s new position as liaison between the Centaurs and the Council is not just a “looks good on paper” kind of promotion. It will allow him to continue his attempts to thwart the mistakes of old from being repeated again. The only problem is, how can they be mistakes if they are what brought his mate into existence?
Luan spent centuries thinking he’d always be alone, destined to be mateless. When his brother finds his forever love, it sparks hope. And now that he’s scented his mate, he couldn’t be happier.

Only one problem: Luan wants to protect his mate at all costs, including his job. If only it were “just a job” and not a mission to keep shifter kinds safe from the unthinkable.