Sir Pentas represents the merged identity of twin brothers Ena and Dio, operatives within Flect Turn's anti-Quirk terrorist group Humarise. They exhibit fair skin, indigo bowl-cut hairstyles, and yellow reptilian eyes ringed by dark purple markings, accentuated by prominent fangs. Their typical uniform features simple red and white tunics with gray boots mimicking snake scales. Trigger enhancement mutates their physiology toward a serpentine viciousness: fresh facial markings surface, their hair spikes violently, their mouths stretch ear-to-ear, and their teeth sharpen further. The twins share identical personalities—erratic, excitable, and prone to maniacal laughter in battle—while displaying fanatical loyalty to Flect Turn's cause. Despite wielding Quirks themselves, contradicting Humarise's genocidal mission, they joined believing they would be spared as "worthy" survivors for the new world. This allegiance stems purely from self-preservation rather than ideological conviction. Their Sword Kill Quirk morphs their arms into extendable bladed limbs for slashing, grappling, and rapid aerial maneuvers. Trigger amplification boosts this power, enabling up to seven simultaneous blades—including growths from their upper back and mouth—while augmenting their speed and strength. During Humarise's Trigger Bomb operation, Sir Pentas defended headquarters against hero incursions, clashing with Katsuki Bakugo. They initially pressured him with enhanced agility and coordinated strikes until Bakugo collapsed structural columns to trap them under rubble. Injecting Trigger to break free and escalate their assault, they still fell to Bakugo's countertactics: he redirected their momentum to slam them into a cavern wall, then immobilized them with his Howitzer Impact blast beneath debris. Post-Humarise's collapse, the twins were apprehended with other survivors.