Ritual Magic - Eileen Wilks

Not really in the romance category in this book. Lily and Rule have one encounter but it's more to get Lily to cool her jets. Past enemies and frenemies are in this book. And even though in our world it's been years from engagement to marriage, to them it's only been about year and they finally tie the knot which seemed to be the shortest chapter there. Great series - one of my favorites.