You can thank  silver144 for this one, he's really dedicated to share with world some of his female fights kinks

Two noble boys couldn't agree which one has better mares, they decided to battle on a neutral ground, away from their parents eyes. Carus, son of a rich merchant, has bigger stables, but hes mares are accustomed to luxury and simple tasks. Does his greater numbers win agains horses of Claudius. They are outnumbered but those are mainly farm animals, rized to pull plows and carts.

Their horses are loyal to their masters, they will do everything to please them, no matter the cost.