Sesshomaru could claim that his desire for Tetsusaiga blinded him. He could claim that he did not expect her to appear as she had, human, and beside his loathsome brother.
He could even claim that because she is human, he paid her no mind whatsoever.
Truthfully, Sesshomaru knows her the moment he parades up on the shoulder of the Oni.
Her unique vibrations, her aura, her bright blue eyes…he knows her.
And for the first time her presence is not a calming blue for him. All he can feel, all he can see is a haze of wild, red fury.
His father.
Tetsusaiga.
Her.
His bastard brother takes all for himself, and Sesshomaru is left with remnants.
Through his haze he feels ill, the scent of his acid sickening.
Why am I doing this?
He asks himself this as his acid falls upon her in a spray of evanescing green.
With his own hands he would snuff out the one life he yearned for more than any other.
Why?
Why?
Why?!
Sesshomaru is tormented and liberated, both, as she burst forth from acid-melt and bones, glaring at him with irate blue.
The sentiments are fleeting as he grows larger, filling the void of his fathers belly with his youki and his rage.
He is set to destruction.
…one day, he will thank his pestilent sibling for saving him from his vengeance.
Fire burns across the open end of his severed limb. His life-blood pours from him as a gushing spring, dyeing his fathers bones and the ground ruby, and one might believe it would only serve to add to his already red-hued fury.
In truth, it brings his awareness back to himself, back to reality.
Sight and scent and sound return to him with forceful clarity.
And with such clarity, he knows he must retreat.
To save her life.
To save his own.
He will retreat.
But he will watch.
And he will know her better still.
Perhaps…this time…from a distance.