Both, who both?

"Welcome home, Siel." The voice, so reminiscent of his dream, whispered in Cassiel's ear as he turned on his toes to face the source.

Before him, he beheld a woman's silhouette, her form shrouded in shadows. The outline of her figure hinted at an air of elegance and mystery, and the enigmatic aura surrounding her was impossible to ignore.

Cassiel's heart quickened, as he felt a strange resonance with this figure, as though he had crossed the threshold into a world where dreams and reality intertwined in ways he couldn't yet comprehend.

"Mom?" Cassiel's voice quivered as he called out to the enigmatic figure before him. Uncertainty and emotions warred within him, and he was unsure of how else to address the woman who had spoken those hauntingly familiar words.