The Yashahime SessKagu fic I will probably never write, so feel free to steal the idea:
Kagura is the wind. Her mind, her consciousness, and her heart all disintegrated and became the wind when Naraku killed her.
As the wind, Kagura can watch. She can act. She can protect. She can follow those that interest her, and what interests her is Sesshomaru.
Sesshomaru does not seem to know she's there, but sometimes she pretends he does.
(Sometimes, he looks at a rustling breeze for just a moment too long, and she hopes.)
One day, as the wind, Kagura gusts over a battlefield of dead men and remembers puppeteering the corpses of wolves.
She learns that the wind can inhabit empty bodies the same as a soul. (The wind is her soul; her soul is the wind.)
Kagura walks among the living again, but she walks as a corpse.
And she remembers that Sesshomaru can unmake corpses. The sword that could not save her then may be able to save her now.
So Kagura, wearing the corpse of a man, tries to find him; but he avoids humankind and their squabbles, and is too far away for this broken body reach.
The wind leaves the fallen samurai to the crows.
Kagura tries again in the body of a woman in a village not so far from where Sesshomaru travels. But humans do not take kindly to a corpse walking away from burial, and they overcome her.
Kagura tries again. And again. And again. A lord's daughter. A failed priestess. A commoner. Beautiful creatures, at first, but now she settles for whatever woman can walk free of a village. Sometimes, whatever man.
None of them make it to Sesshomaru.
Then one day, there's a woman wading into a lake, succumbing to melancholy.
Soon, the wind breathes life anew into water-logged lungs, and then aching feet run.
And he doesn't believe her.
Not until he withdraws a red-striped fan from within his armor and holds it out to her, challenges her to prove she is the wind he'd once known.
And Sesshomaru draws Tenseiga, revives the body, summons a heartbeat, and Kagura destroys the human soul that attempts to return— forever.
The wind has a body. A human one, but it wil do, and that is enough. Sesshomaru certainly thinks so.
In time, Kagura bears him two daughters. Twins. He does not care that they are hanyo; he cares that they are hers.
But the body is weak from the strain. Rin is helpful, and so are all her former enemies, but it is not enough. The body dies, the wind gusts out from its shell, and Sesshomaru takes the children.
Kagura tries again. And she does not have to try hard; Sesshomaru slaughters a pretty young woman for her and waits, holding their children.
They are together again on the same night of her death.
A wetnurse is employed. Kagura and her human body live in the Castle in the Skies. It feels like home.
Sesshomaru's mother likes her quite a lot, and the sentiment is mutual. She wonders if one day Kagura will be able to find a demon body to call her own.
But that is a matter for another time.
When the children are old enough, they travel with him. All is well. The children are happy, they are free, and that is all that matters.
Eventually, the human body grows weak again. Sick. It perishes, as humans do, and Sesshomaru sets out to find her a new form. He leaves the children alone with the toad for two days.
When they return, one is missing. The forest is burnt black. Setsuna is inconsolable. Jaken is dead.
Kagura hates herself, but Sesshomaru hates himself more.
