I've been slowly rereading the Arrows of the Queen trilogy and thought this would be an awesome AU for Emma and Regina. Some story elements and lore have been changed or removed to make this as simple and non-confusing as possible for new readers, but a quick rundown of the basics you need to know for this world:
Valdemar: A kingdom, with Haven as its capital city, always ruled by a Queen. The Royal Palace and the Collegium are located atop a hill in the center of Haven.
Heralds: The peacekeepers of Valdemar, every Herald is paired up with a Companion. As young trainees, they attend classes in the Collegium. Upon graduation, they become full Heralds and patrol the kingdom on circuits.
Companions: Guardian spirits born in the form of silvery white horses with wise blue eyes. They can sense when children are born with Gifts, and when the child is old enough, each Companion Chooses one to be their Herald and brings them to the Collegium for training. They communicate telepathically.
Gifts: Psychic abilities that some people are born with, which makes them candidates as Herald trainees. A Companion Chooses them and brings them home to the Collegium to begin their schooling and training.
*Telepathic dialogue is in italics and is bookended by colons. Heralds and Companions all have the ability to speak telepathically amongst themselves.
::Two colons are used when Companions speak telepathically.::
:Single colons are used when Heralds are speaking telepathically.:
"You hated me in the beginning."
"I did not hate you!"
"You wouldn't even look at me!" Emma laughs, pulling away when Regina swats at her shoulder. They're laid out side by side on a heraldic blue blanket, dressed in their simple summer white sleeveless tunics and breeches, enjoying the afternoon sunshine after a particularly long day of teaching classes. Henry, their rambunctious six year old, frolics around in the grass nearby with little giggles of laughter, playing with some of the young white foals that had been born that very season.
"Bug, she hated me in the beginning, right?" she asks, turning her head to look towards the mass of gleaming white just a short distance away. Two heads lift into the air where their Companions, Mercy and Bug, lay snuggled up on the grass, the mare looking amused while the stallion snorts in her direction.
::She did not hate you in the beginning, Chosen,:: the stallion's warm voice floats into her mind.
::I believe her first thoughts were that you were 'awkward but cute,':: the mare supplies helpfully, her voice entering both their minds, to which Regina props herself up on her elbows to glare at the female.
"You're such a traitor, Mercy," she complains, getting nothing more than a whicker of laughter from the mare. Companions generally only speak to their own Herald, but Mercy likes to break the rules every so often and communicate telepathically with the blonde to ruffle Regina's feathers.
::You were young and in love without even knowing it,:: Mercy sniffs, amused, as she stretches out a little and rests her long neck over Bug's flank again, her belly heaving softly with a contented sigh, round with foal. The stallion lips affectionately at her mane and winks an eye at his blonde rider.
::We've certainly come a long way, haven't we, dearheart?:: he murmurs softly. Emma smiles and projects a wave of love in his direction as Regina huffs dramatically and burrows into her side, head resting nestled against Emma's chest. Her wife acts disgruntled and grumpy but, much to Emma's unending amusement, she is almost always the instigator of affection and body contact.
"Mama! Mommy!" There's a booted foot stepping uncomfortably on her bladder for a moment before Henry shoves his tiny body between his mothers and snuggles right in with a contented sigh. With an arm around her wife and her son, Emma grins over at Bug.
:That we have, Bug. That we have.: