The first spell was cast by Voldemort. As was always the case. The fiery red beam streaked from his ebony wand towards the two males, one with emerald eyes flashing and the others blond hair highlighting the darkness. Voldemort would always be the antagonist, it was the principle of the thing. Not that the resident protagonist was unprepared, he just chose to allow Voldemort to commit himself.
Their spells flashed continuously, the red streaked amidst the green of the two male's spells, because Merlin knows we must keep to our color symbolism.
Harry's spells were forces of raw power, each in its own right enough to knock a less powerful opponent off his feet. And, though Voldemort might be a few to many twigs short of a broom, he was a powerful wizard. Draco's spells, while not as physically powerful as his mate's, were sneaky. Entwining with Harry's spell to inflame with a nascent oil based spell to increase the damage. And finally Kagome. She practiced her own type of spells, not specific to a certain affect, but rather streams of pure light.
As the fight continued, Voldemort's patience waned. Though he was holding his own, he shifted away from the death spell. The incantation was too long, for one thing, and it never seemed to actually hit for the other. Previously he had been focusing on Harry as the main source of his ire. All of his spells were directed at him, practically ignoring the other constituents. That is why, when he doubled his original spell with a hidden second towards Draco, they were caught off guard, arraigning themselves around Harry.
Expelliarmus!
The spell was almost an insult, a reminder of Harry's past weakness.
The second spell was almost a whisper, a sibilant hiss in the dark.
Sectumsempra.
The spell streaked towards Draco. He was already blocking the disarming spell aimed at Harry, at the same time Harry was, focused on that. Only Kagome saw, only she could move.
Throwing herself in front of Draco, the spell missed his unguarded throat and hit her torso in a straight cut across.
Time paused, then crashed. The earth shook, Draco shouted, catching Kagome as she fell. And Harry? Harry roared, scales erupting across his face and exposed arms. Power even beyond his previous power barreled out of him at his mate's attacker. Hitting Voldemort in the chest mid victory snort and throwing him into the wall behind him. Before he could even think to cast again his body was torn apart in the fire of draconian anger. Disintegrating into a small unimposing pile of ash.
Which was ignored. Blatantly. Harry was on his knees clutching Kagome to his chest. His eyes were flashing, his pupils dilated as he "went dragon." He ignored the real world, clutching at Draco's mind for support. Desperately searching inside Kagome for her life core. Finally, he saw a faint glimmer. A thin strand of green, flickering slowly. He pulled it to his, trying to combine them. It was not enough until Draco intervened. Carefully melding his mind with the mind of Harry, he caught his attention.
"Here, catch" he said calmly and without a care for his own well being, threw his life core at Harry. Harry caught it, with a snort at Draco's almost Gryffindor action, and began braiding the three strands together. Carefully, oh so carefully.
When he finished, he watched as Kagome cautiously opened her eyes, amongst the living once more.
Before she could utter a word she was caught up in Draco's arms from behind, as Harry grabbed her chin for a fierce kiss.
"Don't ever do that again" Draco growled into her hair.
"Our lives are one. If one goes, we all go" Harry spoke deeply, stroking Draco's hair as he pulled Kagome close.
"As it should be" Kagome answered.
They turned as one as the door burst in to admit the Order members, too late as usual.