The Department of Mysteries is in chaos. Sirius moves through it like a man half-drunk on adrenaline, half-feral. He's laughing- actually laughing- as he duels, the sound sharp and reckless, the kind that comes from a man who has spent too many years caged and has no patience left for fear.

Bellatrix’s voice cuts through the chaos like a blade. “Sirius,” her voice is an eerie, lilted sing-song. Almost wanton, alluring like a siren in the way that makes your stomach turn.

His grin flashes, wild and bright, as he pivots to face her. Of course it’s her. Of course the universe would bring her here. She looks madder than he remembers, dark hair plastered to her face with sweat, eyes alight with devotion that has long since rotted into obsession.

“Missed me?” Sirius calls, wand raising as another spell sails past his shoulder and explodes against the wall behind him.

They circle each other near the great stone archway, the Veil whispering its secrets in a language that makes the back of Sirius’s neck prickle. Bellatrix laughs, high and thrilled. “Still joking. Still stupid. Azkaban didn’t fix you after all.”

Her curse comes fast. Sirius deflects it easily, too easily. He glances aside, just for a heartbeat, and sees you fighting not far away, caught in the same storm of spells and shouts. You're alive, that's all he needs to know.

“Come on, Bella,” Sirius taunts his cousin, breathless and bright. “You can do better than that.”

Bellatrix's smile sharpens, eyes crazed, and she raises her wand. "I'll do what dear aunt Walburga should have done years ago when she blasted your name of our sacred tree!" Her wand crackles with green lightning, the kind that makes your stomach drop, the kind that kills, the forbidden curse on the tip of her tongue.