He opened his mouth to scream, but it was too late. Snape had one arm around his waist, holding his arms down and his other hand over his mouth before Harry could even blink. The vampire tilted the boy's head back against his chest and to the side, exposing his throat and the mark Remus had left there.
Harry felt a warm tongue slide against his skin and shuddered. Part of his instincts were telling him that Severus was an acceptable mate, powerful and fearsome. But the rest of him was screaming that this didn't feel right. He did not want Snape his greasy, old, most-hated professor licking him!
He felt teeth scrape against his skin and flinched. Snape biting him would only exacerbate the situation. The other creatures, furious that not only one but two people had managed to mark him, would become infuriated. Their fury would provide them with an adrenaline rush. The subsequent power boost would enable them to escape as well. They would kill each other and take most of the student population with them.
He tried screaming again but the sound was too muffled and the man's bloodlust too strong for it to have any effect. Harry's eyes swept the room wildly, looking for any possible solution. The other creatures were trying to get out. Harry knew that if even one of them managed it he would probably be killed. They didn't want to hurt him, but their rage would blind them to the fact that he was standing in between them and their prey.
His eyes landed on Neville. He was up, the water from the lagoon surrounding him, allowing him to breathe. He was pressed against the glass like the others but seemed to be much calmer. His gaze was focused intently on Harry, not giving Snape a second thought. Harry closed his eyes; please let this be the right choice… He sent a sharp command to the Room of Requirement, desperately hoping it would respond to his thoughts. Please, I need him. And just like that, Neville was freed.
The glass on Neville's cage dissolved and with a loud rushing sound, the water in his enclosure spilled out, carrying Neville with it. The ashray stood, a circle of water remained around his neck so he could breathe. He made a few complex motions with his hands and the water surrounded Snape, separating him from Harry.
Snape fell to his knees, agony plainly written on his face. The lack of air didn't bother him, he didn't need to breathe, but the pain was excruciating. Water was not fond of vampires. The distaste was mutual. Running water is natural and pure, a symbol of life. A vampire is dark and unnatural; its very existence defies the laws of life and death. It wasn't anything as dramatic as melting, but there was a lot of screaming involved.
The water carried Snape back to his cage and trapped him in a far corner before pulling away from his skin. The screaming stopped, but the man was soaking wet and clearly still in pain. Snape stayed in the corner, his eyes fixed on Harry and Neville. Lust and rage warred in his eyes. The need for revenge won out but he could not move. He was not willing to put himself through that kind of pain again.
Harry ordered the Room of Requirement to seal off the pen before Snape could decide that killing Neville and taking Harry was worth the price. Today sucked. The stress just kept piling, only to crash down on him when he wasn't keeping it balanced. He slumped down and would've fallen had he not been caught by a pair of strong arms, one wrapping around his hips, the other around his shoulders. He was pulled against a warm body and felt a chin set lightly on the top of his head.
"Hello Harry."