They didn't normally spar together; not even during the war.
While Azura was no slouch with either the lance or the naginata, her main role had been to use her song to support her allies. Corrin, on the other hand, was trained from a young age to be a frontline fighter; from the moment it was just the three of them against the world, to finally facing the Silent Dragon, he was always in the thick of it, golden Yato flashing.
That was almost six years ago though; while Corrin had kept up his training routine, Azura had let herself slack off; focusing more on politics and running the castle then martial pursuits, and while her dancing kept her in shape, she did not miss using a weapon.
So it was a surprise to Corrin when she came to him and asked him to spar with her for the first time in years. Still, he agreed, and decided to ask 'why' later. He always enjoyed spending time with her, and it always paid to not let your skills atrophy after all.
Of course, five minutes in and it became apparent just how far she had let herself ago.
Azura, dressed in a Hoshidan training uniform called a 'gi,' grunted as her back hit the dusty ground for the third time.
"Alright, let's try that again." Corrin, dressed in trousers and a tight shirt, said as he picked up her quarterstaff, "The more we practice, the more your body remembers the old moves."
Azura let out a sigh as she got back up, holding out her hand to him, gesturing for Corrin to throw her back her staff.
He complied, tossing the solid oak to her as he readied his own staff. Slowly, they began circling each other, staffs at the ready. Corrin took note of her body language; she was remembering her old training, though it was slow going, and to a trained fighter like him, she was telegraphing her moves to him, as clearly as the silver after Jakob was through polishing it.
When she made the first move, he was ready.
"Ow, ow, ow…" Azura said rapidly as Corrin applied the ointment to her bare back.
"I'm sorry." he said apologetically, "But I did say it would sting."
"Don't apologize." she said, wincing, "I'm the one who asked you to spar with me after all."
They were both sitting crosslegged on the ground, with Corrin applying the healing ointment to bruises and a few cuts.
"Are you sure you don't want me to sue a healing staff? It works better than this goop." he asked, to which she shook her head.
"No need to waste a charge on this." she said, "Not for something this small."
"You're worth it though." he countered, pulling her shirt back down and wrapping his arms around her, "Well, that and it would look bad if people ask why the Queen has bruises and their answer is "Because the King beat her up." Might send the wrong message."
She let out a short laugh at that.
"So," she started, "How well did I do?"
"Honestly?" Corrin began, "I knew you were rusty Azura, but we have a lot of work to do to get you back into fighting shape."
She sighed and leaned back into him.
"Just as I expected then."
"Would you mind telling me why you wanted to do this all of a sudden?" he asked, "I've been saying you should take up sparing again for years, but you never seemed interested."
"I suppose you deserve an answer." she replied, "Do you remember how, after we were married, we decided to wait a few years before we have children?"
"I do."
"Well, with Valla finally stable again, and both of us more comfortable in our roles I was thinking… I was thinking now would be a good time."
Corrin smiled and kissed her head.
"I've been thinking the same thing; but that doesn't explain why you asked me to knock you around though."
"You did not knock me around." she said in a faux affronted tone.
"Well, what would you call me knocking you on your ass all afternoon while you didn't lay a finger on me?"
"An unfair advantage." she joked, "Considering you're practically the strongest man alive. We are getting off topic though; I asked you to spar because… because I want to be able to protect any sons or daughters we have. I know we have bodyguards but… our extended family doesn't have a good track record with keeping children safe."
Corrin grimaced at that. She had a point; both Azura and himself were hostages, he taken from his birth mother, and she taken in retaliation. Though he had been deceived into thinking he was a member of Nohr's royal family by blood, and so he had never known he was a hostage, Azura did, and despite the kindness shown to her by their Hoshidan family, the stigma and label of it never went away.
Still, she had a far better life in Hoshido than she ever would have in Nohr, between the chaos of the Concubine Wars, and royal princes and princesses dropping like flies, and to be held in the hand of Anankos' puppet. The worst Hoshido had to offer her was nothing compared to that. Unkind comments and distrust were preferable to death, and being accepted as a member of the family in all but name had encouraged Azura to assimilate into Hoshidan culture.
The revelation that Mikoto was her aunt, her mother's younger sister, had made her memories of Hoshido fonder. No more was Mikoto just a kind queen who had taken pity on a scared and lonely Azura, who had been abducted to be used as a prisoner to exchange for Corrin, or to get back at Nohr. Despite her eccentricities, Mikoto was an intelligent woman; she had to have known that Garon would not give back her son, not for Azura, but she had paid the Kogha mercenary to abduct her anyway, in retaliation. That she had come to love Azura was, for Azura, had been a happy side effect. That was not the truth however.
The truth was Mikoto knew that Azura was her niece, and despite her own loss, had made the effort to take her out of a bad situation, and give her a home in Hoshido out of love for family. That revelation had brought Azura much happiness in the years to come, that she had a blood relative alive, and who cared for and raised her.
Still, that did not change the fact that both Corrin and Azura were taken as children, and the fear of their own children being taken away from them, was one they both shared.
"I wanted to see how much I would have to regain." Azura admitted, "How much I had allowed peace to let my skills go to rust, so that after I have our first child, I would know how much work I would have to do to regain my edge. After today, I clearly have a lot of lost time to make up for."
"Then I'll help you."
"Thank you." she replied with a smile.
"So…" he began, his voice lowering to a husky whisper, "Tonight, shall we get started on that baby?"
"Normally, I would say yes…" she started, "But I'm pretty sure I'm too sore tonight after that thrashing you gave me."
"Oh… how about a hot soak in a bath and then cuddling ourselves to sleep?"
"That sounds perfect."