The Veil Runners

When the border between worlds begins to tear, Tamsin Vale-a courier who can sprint the dangerous Veil-takes the job no one will touch: escort a shadow prince and a forbidden crown-shard across a road that eats the unwary. Prince Rhun Ashkar is everything Tamsin distrusts-secretive, lethal, heir to a court built on half-truths. But the Wardens are sealing towns behind iron bells, the haunted inn that anchors the route is waking, and there's only one bed when the inspectors come knocking. Every promise feeds the darkness hunting their names.
To smuggle hope, Tamsin and Rhun will bargain with ghosts, outpace a choir that sings with stolen voices, and risk an oath that binds their costs together. The crown-shard can heal the Veil-or shatter it-and both realms want it. Refusing the choice may be the only way to save them all. The Veil Runners is a sweeping romantasy about the logistics of love and the magic of kept vows/protective meets razor-sharp courier on a perilous road, where found family is forged mile by mile.