Severus was so overtaken by the desire and the hands that made him feel the most exquisite pleasure he had ever felt. When Remus' finger stroked over his opening, he yelped, although wanting it so very much. Severus was a bit tense, he had never let anyone take him that way, it was a part of him he didn't want to offer to somebody who meant nothing to him, not like Remus did.
Severus was kissing Remus back, engaging in a devouring kiss, when Remus suddenly tensed and an expression of fear replaced the fire in the golden eyes. For a moment, Severus didn't understand, not until Remus cried out. A look over his naked body explained it. The full moon hung, white and round and destructive on the black winter sky.
'No! Remus!' Severus echoed Remus' pained denial of the inevitable. Then Lupin fell down, dropping from the bed, shaking from pain and the brutality of the transformation. For seconds Severus was unable to move. On the floor Remus lay, shaking from pain, as the curse pulled and snapped and wrecked his body into another shape. Severus stared, helplessly, as Lupin's face elongated and white teeth grew sharp and long. Fingers contracted and became claws. The noises Remus made was worse than anything. This was painful, even more than a Cruciatus curse, that Severus was certain of.
Severus managed to drag himself out of the paralysis of shock and phobia, sending one look at the man he thought he would come to regard as his lover. When Remus' skin began to sprout fur, Severus gathered what he could reach of his clothes and ran.
He didn't really feel the stairs$ under his feet, all he cared about was to reach his wand in the sitting room. He could keep the dirty beast away with that, did he not manage to get out before the animal had finished it change and would come for Severus. He pulled his jeans on, the pants had disappeared. He put the wand in the back pocket as he dragged the tunic over his head. His boots were nowhere to be seen. ''Accio cloak,' Severus managed and ran out in the hall to get his new travelling cloak. He didn't want the beast to ruin it.
He turned at a small sound from above. On top of the stairs, a giant golden-grizzled wolf stood, looking down at him.