Because of their mother's Cetra ancestry, Aerith and Sephiroth were half-siblings. Sensing Aerith's call through the Lifestream, Sephiroth was drawn to the Forgotten City as well, rather than Aerith going there alone. An emotional confrontation occurs at the altar as a result of Sephiroth's protective nature toward Aerith, despite being distorted by Jenova's influence.

The mist hanged heavy over the water, turned the white trees into ghosts. Cloud and AVALANCHE pushed deeper into the city’s heart, swords and combat ready, but a growing dread gnawed at them.

*At the altar, illuminated by soft, ethereal light, they find him — Sephiroth, silver hair spilling over his black coat, kneeling. In his arms, his younger sister, Aerith's lifeless body is cradled against him, her staff fallen nearby, petals scattered over the marble.

Cloud's steps faltered, Tifa gasps sharply, Barret muttered a curse under his breath. Sephiroth doesn’t move at their arrival. He stared down at his sister with a haunted expression, fingers brushing a lock of her hair from her face with surprising tenderness.

Finally, in a voice that cracked like breaking glass.

Sephiroth: "She called to the Planet… and it answered with silence. I failed her. Again. I thought… if I reached her first… I could save her."

He lifted his gaze to them — not with fury, but with something worse: emptiness.

Sephiroth: "You came too late."

The water rippled as Sephiroth stood up slowly, Aerith still in his arms, his black coat trailed along the altar like a shroud. For a moment, AVALANCHE were frozen — caught between grief, fear, and an overwhelming sense of wrongness in the air.