His intention may have not been to kill her but Fenrir wasn't letting up on his sister. He found it interesting... To watch the light slowly fade from her eyes and the hand that clawed at the one holding her throat? Began to slow its movement, her lips were already turning a pale blue color, her vision was becoming blurred over and then a echoed growl came and a black mass was in her sights which led to Fenrir releasing her, her head slamming to the side from the force.
Embry was the least of Fenrir's worries after the attack laid on him by the dog. He went to attack it but seen the transformation into Wilberforce? Who then sent a curse his way. Fenrir attempted to dodge but failed completely, the Sectumsempra hitting him in the shoulder but luckily he missed by a hair, the blow that would cause amputation. But that didn't mean Fenrir didn't feel the pain or he wasn't suddenly gushing blood.
Embry laid on the ground, wheezing loudly, her hand to her chest as she fought to breathe. Hearing Sirius? It only gave her more initiative to fight but she was having a hard time. Her head was pounding and she was exhausted it felt like, she wanted to sleep. But she was scared. Had he hurt their baby? Did he hurt Sirius?
Fenrir got back up and the other curse? He was able to dodge that one completely but the skin on his back though. It came close. At the threat, Fenrir barked out a laugh, his hand holding his injured shoulder.
"I should have known, Black." His voice was razor sharp. "I always knew there was something not right about you. I could smell it on you. So you cheated death and as a coward, hid amongst us? I knew you were leading us the wrong way on purpose." He watched as Embry's hand went out and she whispered the name, only confirming that the man before him was indeed Sirius Black. "If the elf hadn't tipped me off, this did... You know what I'm going to do? Hm? I'm going to kill you and right before you reach the brink of death, I'll allow you to watch me rip the bastard out of her belly and devour it."
His wand came out and the Cruciatus was thrown, although it seemed to miss and it was then that Fenrir ditched the wand completely and turned into the beast he was, gripping Sirius by the neck with his good arm and throwing him like he was a empty sack against a near standing tree.
While Sirius was down, he only finished what transformation he was capable of at will without it being a full moon. Fenrir harbored and perfected his lycan blood. He could bend it in ways that most couldn't. He could manipulate it and while not turning into a full fledged werewolf without the power of the moon, he could still tap into his inner beast who had a unsatisfied thirst for human blood and hunger for the human flesh. The sight of him was terrifying and wasn't not a pretty sight. Fenrir as human was quite an attractive older male but now he stood would access hair, larger muscles, teeth and rock hard and blade sharp nails.
The two seemed to circle each other, like dogs about to fight for territory and Fenrir was hit again with a spell. Magic was his one weakness. While he was capable of spells and unforgivables, his magic was limited and his dueling poor. He relied more on his strength and physical prowess than his magical side... he despised wizards.
His body was shot down quite a few times with the hexes and all the other things that was thrown at him but he still managed to get Sirius pinned. He was going to make a killing blow, teeth aimed at throat... Until someone jumped on his back.