Author's note: I'd apologize, but I'm not particularly sorry.
Disclaimer: Harry Potter belongs to JK Rowling. No profit is being made from this work.
Enjolras is dead.
People are screaming and throwing curses and scrambling to find cover but Combeferre doesn't notice any of it because Enjolras is dead and it wasn't supposed to go this way, wasn't allowed to go this way, and Courfeyrac hasn't been seen in hours and everything is falling to pieces and Enjolras isn't moving. Combeferre's holding his wand in one hand and he clenches his fingers around it as tightly as they'll go, not feeling the pain as his fingernails dig into his palms and his muscles protest the strain, not feeling anything, and the world is turning red around the edges. Enjolras is lying in front of him, lying sprawled out where he fell, a fierce expression on his face that will never again smooth out or fill with passion or change at all because Enjolras is dead.
He doesn't notice the people around him until someone shoves him aside just as a bolt of puce-colored magic shatters the cobblestones a fraction of a centimeter from Enjolras' limp hand. A shard of stone flies into Enjolras' face and nicks his cheek, tearing rapidly cooling skin, and suddenly Combeferre's world snaps back into focus. He stands, ducks another curse, and narrows his eyes. The world is still red, will always be red, but he can see past it now, can see the black robes of the enemy down to the tiniest detail. Of its own accord his hand snaps up and a curse flies from his wand, cast wordlessly and aimed with deadly accuracy. A soldier falls before he can scream and Combeferre bares his teeth in a mockery of a smile. He stoops, brushing a hand down Enjolras' cheek and gently closing his eyes for the last time. He pries his friend's fingers open and plucks Enjolras' wand from his grip, pressing his own into its place and closing Enjolras' slender fingers around it. He lowers Enjolras' hand back to the ground and straightens, turning once again to face the oncoming soldiers. He raises Enjolras' wand and it feels right in his hand, feels eager to avenge its owner, feels alive. His friends back away as he advances on the enemy.
Combeferre doesn't lose himself in the fight. He throws curse after curse, calculating angles and aiming for weak spots with clinical detachment. He's studied the effects of all these curses, has written pages of essays on the most vulnerable parts of the human body, has practiced wand movements for hours, and now he puts his education into practice and before him the ranks of soldiers fall back. He ducks away from their curses and does not bother blocking, and in his hand the wand is warm. It is a hopeless fight, that he knows, but he will not betray his friend, his brother, by standing down. Combeferre has never been ruthless, has always valued life, but Enjolras' wand is hot in his hands and the world is still red and behind him on the pave stones Enjolras is dead. He keeps fighting.
Combeferre wakes in a cell, wandless and in chains. He thinks he is alone but he does not move, does not call out, does not test his hypothesis. His eyes adjust to the dark after a time but he barely notices, because he's alive and it wasn't supposed to end like this. He was supposed to die on the streets, was supposed to perish for the cause, was supposed to join Enjolras. But Enjolras is dead and Combeferre is alive and he doesn't know how it could all have gone so very wrong.
Time passes. He drifts in and out of consciousness. Someone comes into the cell at one point but Combeferre doesn't speak, doesn't look up, doesn't move at all, and eventually they leave. He waits.
They set him free eventually, push him out of the cell into the sunlight, leave him with nothing but his wand, Enjolras' wand, and a complicated tracking spell that takes him three days to remove. He doesn't speak, doesn't acknowledge them, doesn't look anywhere but straight ahead. People shy away from him on the street and he doesn't see them. He passes through the streets like a ghost, legs moving by rote until they take him to the apartment he shared with Enjolras. Combeferre stares at the door, hands trembling, and turns away.
He sleeps outside that night, layers of charms covering his body to protect it from the elements and his fellow human beings. In the morning he withdraws all his money from the bank and vanishes into muggle Paris.
When he next steps into the wizarding city even his friends do not recognize his eyes.