Seihitsu no Hassan is depicted in a dramatic pose that emphasizes mystery and precision. The figure wears layered, traditional robes that flow with an almost wind-swept energy, rendered with careful sculpting to show delicate fabric folds and subtle weathering. A long cloak or mantle sweeps behind, with intricate patterns and a restrained color palette of midnight blues, charcoal, and crimson accents. The character's face is partially obscured by a hood and multiple hidden blades are integrated into the silhouette, hinting at the Hassan lineage’s mastery of deception. The base features sacred text motifs and a stone-like texture that grounds the motion, while the overall balance conveys a poised, deadly elegance suited to a legendary assassin.

Seihitsu no Hassan is one of the famed Hassan line in Fate/Grand Order, an elusive order of assassins famed for their many disguises and chilling precision. In the stories, this servant moves through shadows with uncanny calm, using misdirection and swift blade work to outwit powerful foes. Her multiple faces symbolize the many masks she wears to fit different missions, each face reflecting a different aspect of her cunning. While she rarely speaks, her actions reveal a relentless determination to complete her contracts under the watchful eye of fate. Through trials and battles, she demonstrates the paradoxical blend of grace and deadly efficiency that makes her one of the most enigmatic servants in the series.