Belenus and Brigantia
Benenus and Brigantia are radically different in their interests (he's the Lord of Light, she watches over animals and waterways), but they've found common ground outside the standards of the Celtic pantheon. They share the realm known as the Isles of the Blessed, the resting place of mortal heroes who've actively sought to do good in their lives.
The realm's almost constantly sunny, and when night comes, it's brief and cool. Legend says that night arrives only when Belenus has stepped away from the realm to do the bidding of the Daghdha (though it might arrive early if petitioners or visitors offend him in some way). Rivers crisscross the land, sparkling blue reflecting into the sky and echoing through the air. And despite the fact that sheep, cattle, and their keepers are common throughout the realm, it very much seems as through a body's alone. The center of the realm (and the home of the powers) is a hillock called Sunswatch.
Beltain Firebrow serves the interests of Belenus in the Isles of the Blessed, maintaining the woods and groves against those who might try to despoil them. Beltain's rough and course, and he ain't afraid to use physical force when necessary, but underneath it all beats a heart of pure gold. He can speak to any beast he sees, whether it's natural or magical, and no beast can attack him.
Brigantia's proxy is Alaina nic Gwydion, a charming and steel-willed woman unafraid of anything. While in the Isles, she can't be touched by any forged weapon, and her eyes have the power to charm any male who looks into them. Still, she's friendly enough until pushed. She usually watches over the herds, but she can also be found at the Sunswatch after finishing her duties for the day.