Disclaimer: I own nothing, nor am I making any money from this story. All the rights and such go to the lovely JK Rowling.
From the sturdy mahogany doors to the left of him came Lily and James Potter, wands out, sparks flying. The man drew his wand quickly and blocked the hexes coming from the two while throwing his own toward them.
"Two against one, now?" the man taunted. "That's not a fair game. Do you really need a woman to help you, James? Are you not man enough to face me alone?" A sneer lay painted on his mouth, turning his skeletal face upside down.
"He's man enough to face ten of you, but I want to help bring you down!" screamed Lily, fighting as fiercely as James.
"I think I've had enough of this foolishness," the figure said as calmly as he would if he were asking for a cup of tea at the local bakery. He pointed his wand at Lily and said," Avada Kedavra."
James dove in front of Lily, taking the spell meant for her. However, as he fell, he took her with him and her head took the brunt of the fall with a loud crack. The man stood beside the two tangled bodies and uncaringly kicked the man from on top of the woman. He looked at her: eyes shut, mouth slack, and her head cracked, the blood spilled forming a halo around her head. As he lifted his wand to shoot another Killing Curse at her to make sure the deed was done, he heard a child's cry from above. Looking around, he found no sign of the dog that alerted the Potter's to his presence, and hastened up the stairs in search of the child the cry belonged to.
Forward, down the hall at the top of the stairs he ran, until he stopped at the slightly opened door at the end. Kicking it open, he came face to face with Sirius Black who was shielding the boy from his view.
"Sirius Black. How noble of you to shield a worthless child."
"Shut. Your. Filthy. Mouth. You will never speak of my godson," replied Sirius, acidicly.
"Ooh. Have I hit a nerve? Who would've thought it would have been that simple? Although, you Gryffindors have always been too easy to read, and far too noble for your own good. Such a waste it would be to spill such fine pure blood. I hate to do it. So much potential you had, Sirius. Such a fine family you come from. You would have been welcomed into the ranks of my followers, like your cousin Bellatrix. I suppose, though, potential remains. So I shall do something I normally do not, and you will see firsthand what a merciful Lord I can be. I give you, now, one chance. Give me the boy, and I give you my guarantee that you will walk out of this house unharmed and be welcomed into the ranks of my Death Eaters."
"While your merciful tendencies have been plain to see, my Lord," said Sirius sarcastically, "I'm afraid I'm going to have to decline. You see, I happen to fancy myself an attractive man, and I just don't think that 'spineless coward' is high up on the lists of women as a desirable attribute."
The man's face of false hopefulness turned to one of abject rage.
"You dare defy me? Your rightful Lord? Avada Kedavra-"
"Expelliarmus!"
The dark figure's face was horror-filled as his curse turned toward him with the sparks of Sirius's defensive spell. He hit the wall behind his back with a thump and slid limply to the floor beneath him, empty red eyes staring unblinkingly at the window on the other side of the room, through which a perfectly full moon could be seen.