All Remus felt was pain. The pain of his broken arm, his transformation, and now his heart. The last few minutes didn't seem real as he searched for the cause. The Ministry men storming into the room, pinning him down, breaking his arm when he tried to fight. He remembered the sound of Peter screaming as he cowered in the corner of his bed. He remembered the sound of James' voice as he tried to hold Sirius back, and then his failure as Sirius yelled out a hex. He heard the soft incantation as the hex was thrown backwards, and the thump of a body as it hit the floor. James and the other men had joined in Peter's screaming, making the room around him buzz with white noise. He gathered his strength and turned his head, his amber eyes meeting his boyfriend's grey ones. The usual light in Sirius' eyes was replaced by a dark, almost foreign fury which was fading fast.
That was when it happened. The unknown Ministry worker had pulled on his broken arm in an attempt to get him up, making Remus flinch as he tried to bite back the pain. Remus saw the angry spark in Sirius' eyes and then it was a blur of black as the boy launched himself towards them. Remus' eyes grew wider as the scene unfolded almost in slow motion in front of him. Sirius' body was shifting in mid air, and his eyes became feral and canine and he hit the Ministry worker square in the chest with all four legs. Remus dropped to the ground as the man flew backwards, his bones cracking, shattering as he connected with the wall. Animalistic sounds reverberated around the room, causing a collective gasp of pure surprise to escape everyone's lips.
That was the night Sirius Black became a murderer. It was also the night he finally completed the Animagus spell he'd been trying to master since third year.