Withdrawing his leg, Harry slipped under the table without waiting for Draco's reaction, moving straight towards his target. Controlling the urges of his incubus part, he freed the button of Draco's trousers and undid the zip gently rather than ripping it apart, which was what he really wanted to do.

The silk boxers he found underneath were not a surprise and neither was their colour of deep green, but Harry was not particularly interested in the soft material. What he wanted was the prize within. He slipped nimble fingers into the opening in the underwear, sliding talon tipped digits gently around what he found. He ran his tongue over his lips as he released Draco's healthy erection from the confines of the material restraining it, and breathed in deeply, taking in the scent of male arousal.

It was all he needed to encourage the incubus form out completely and he felt his chest tingling as the spines erupted, forcing his t-shirt away from his body. It did not escape him that his own trousers were suddenly tight either.

There was a moan in response from Draco, almost as if his lover had felt the change in Harry, but he was too focussed on his prize to take much notice. The tingling of arousal from his companion was enough to keep him very much absorbed. Everything else around him disappeared into insignificance.

If there was one thing that might get him killed one day, it was his fanatical focus when it came to his incubus' needs. Leaning in, he let Draco's scent flood his senses and stroked his lover's erection from root to tip with both his index fingers. The breathy response and the fact that Draco opened his legs wider, slouching in the chair, encouraged Harry in his next action. Placing his hand flat on the underside of his lover's cock he opened his mouth and almost experimentally, stuck out his tongue and ran it over the head.

A hand snaked under the table then and long fingers wrapped into his hair. He took that as a positive response. The taste of Draco was fantastic, alive and real, and it filled his mouth and nose, drawing him in closer as he firmly sucked his prize between his lips and onto his tongue, running the tip down the moist slit.

The incubus had many talents, a very well-designed predator, perfectly suited to all things sexual. He allowed the demon to change him yet further as his tongue thinned and lengthened. He had not employed the more extreme changes the incubus could attain since that first night and this time he did not split his tongue, snake like, but experimented, allowing it to elongate even further, coiling it around the length of Draco's erection and pulling back slightly, tightening his grip.

The explosive groan from his lover and the fingers grasping at his scalp rather indicated that his experimentation was appreciated.

Concentrating, he moved forward again, allowing the sexual energy from Draco to spur him on, and he felt a wave of possessiveness sweep through him as he claimed his lover whole. The momentary gag reflex was ignored as the dark creature in him took over and forced his human reactions to the background. His tongue moved as he used his throat and lips to stimulate Draco, drawing small sounds and movements of encouragement from his lover. Using his hands, he pushed Draco's legs even further apart and slightly up, giving him more access as he buried his face in silk.

Now he upped his pace and began to move his head up and down as Draco surrendered all control to him. Shortening his tongue, he allowed it to split and, rather than coiling it around his prize, he wrapped it much more firmly around Draco's cock and sucked, hard. It couldn't exactly be said he was stimulating his lover in the old-fashioned way, but he held back on the desire to force power between them, he wanted to do this physically.

He might have been mostly under the influence of the incubus, but that did not mean the human part had no needs as well. Touching Draco was a joy that all of him enjoyed.

With his movements and firm tongue, it was not long before Draco was panting and moaning in time with his ministrations. Harry could feel the arousal building and building in his lover and his body vibrated in response. His own erection pressed uncomfortably against the zip of his jeans, but it did very little to distract him.

Slipping his hands further down Draco's legs, under his lover's body, he gripped the firm buttocks and squeezed as he deep throated Draco yet again. He felt Draco's orgasm coming before it arrived and pulled back just slightly, feeling the beginnings of the payoff with relish.

Almost immediately Draco bucked into his mouth, calling out wordlessly as liquid hit the back of Harry's throat. As the incubus drank in the energy of sexual release, the human drank the very physical reaction and all of Harry rode the high. Sometimes he needed this, sometimes he just wanted it, but in this the sexual predator and the human need came together as.

He needed Draco in a physical sense, or his incubus nature would drive him to acts he could barely admit to himself, but he was beginning to realise that he needed this for far more human reasons as well. He refused to dwell on the ideas that flashed through his mind, but they settled at the back of his thoughts nevertheless.

Only as he drew back, tongue returning to its normal shape and size, but still very efficiently removing all signs of Draco's orgasm from his lover's slowly softening cock, did Harry's own state of arousal make it back into his senses. His lover was lounging bonelessly in the chair, barely staying in place as Harry withdrew his support.

Draco gave no indication of moving any time soon as Harry crawled out from under the table. In other circumstances he might have waited for his lover to recover and then request that Draco return the favour, but he was rather too much in need for that.

Sitting on the floor – he really didn't care what impression he was going to give – he fumbled with the fastenings on his jeans, pushed them down and freed his erection from his underwear. He could not help the moan as he wrapped his fingers around his cock. He was almost painfully aroused. He needed his own release as quickly as possible. Pulling his t-shirt up and out the way he spread his legs and fisted his erection firmly, grunting with relief as he felt the beginnings of his own completion.

It took only a few stokes before he was bucking into his hands. It was quite strange to feel his own orgasm in isolation, without his lover's at the same time, but it still took his breath away as he shuddered uncontrollably. Only as he sat there panting did he begin to come down properly and the incubus attributes begin to fade from his body. It took him a long few seconds to sort his head out and he looked up to find hungry grey eyes watching him intently.

"Merlin, you're beautiful," Draco said in little more than a whisper.

Harry felt himself flush.

~*~

It was almost an ordinary morning in that at least Harry was feeling vaguely human after satisfying his sexual urges. He and Draco chatted idly about anything and everything. It was quite simply nice, as Harry enjoyed his lover's company. They were not disturbed until about ten at which point Jeremy announced that Professor Snape was outside. The pair shared a look. The Potions master would only be here for business, it wasn't as if he was the social type.

"Please let him in, Jeremy," Harry said after a few moments.

At least this time they were both fully clothed, except for the fact that Harry wasn't wearing shoes and socks. When Snape entered the room this time, he was carrying a tray once more, but it was covered and the chemical smell that assailed Harry's sensitive nose set his teeth on edge. The Potions master did not appear even remotely surprised to see Draco in the room and Snape acknowledged the member of his house with a nod.

"Good morning, Professor," Harry said, squashing the discomfort he always felt around the wizard so that his darker side would not react.

"Mr Potter," Snape replied in his usual tone, "Mr Malfoy."

"Professor," Draco returned cordially.

"I have been carrying out some preliminary experiments," Snape returned to business immediately, "and I believe I have constructed a potion which should help with some of the more overpowering urges. Unfortunately, due to your unique physiology I cannot guarantee the potency of the mixture; however, I can assure there will be no major side effects. I have also updated the list which I gave you at the time I took the blood sample."

He handed Harry another piece of parchment and, if he had been talking to a Gryffindor, Harry would not have hesitated to leave it at that, but he was talking to a Slytherin, and the head Slytherin to boot, so his eyes narrowed in suspicion. He let his mind run over the first comment carefully.

"So, what are the minor side effects?" he asked bluntly.

Snape appeared vaguely surprised by the question and removed the cloth from the tray with a raise of his eyebrows.

"Possible nausea, light headedness and drowsiness," the potions master replied openly.

"But it might stop me hurting someone?" Harry wanted to be sure he had this correct.

For a while Snape did not reply and continued to arrange things on the tray.

"Although it pains me to say it, Mr Potter," the head of Slytherin said, "I believe you will prevent that yourself. However, the general idea is to make that onus easier on you. With Miss Granger's input a solution presented itself, but the results cannot be assured."

Looking at the goblet of what appeared to be a noxious green liquid, Harry made his decision and he picked it up dubiously.

"Any particular instructions?" he asked as he held it away from his nose.

This close the smell was almost overpowering.

"I would suggest downing it in one," Snape said unsympathetically.

That made Harry grimace, but he was nothing if not brave. He lifted the goblet slowly. The smell was enough to set some of his darker aspects screeching that he was insane, but he put the vessel to his lips and tipped it back quickly. It tasted like nothing on this earth, worse than polyjuice, and that had been bad, and it hit his stomach like a stone, but he finished it anyway.

"You out did yourself," he said when he could finally control the retching that followed, "that was worse than I can possibly describe."

"I'll remember to add essence of orange next time," Snape said sarcastically. "Any immediate effects?"

Harry felt like telling him where he could stuff his 'immediate effects', and it was a very close thing, but he held his tongue. The only thing that he could feel at the moment was the desire to bring back what he had just swallowed.

"The nausea you mentioned," he said slowly, "but I don't feel any different."

"Please record any other results," Snape said efficiently as he replaced the cover on the goblet. "Positive as well as adverse; your reactions could be important."

"Uh-huh," Harry replied, but he was beginning to think that the sick feeling in the pit of his stomach was not going to stop.

In fact, it was getting worse and he looked at Draco worriedly.

"You look almost as green as my bed sheets," his lover said unhelpfully.

For once a snarky reply jumped to his mind, but he had no chance to say it. At that moment his stomach did a flip and he knew instantly that he was about to lose this battle. Without even making a vain attempt to try and maintain his dignity he put his hand over his mouth and ran to the bathroom. The potion revisited the world as quickly as it had gone down as he knelt helplessly over the toilet bowl.

"Uncontrolled vomiting," he heard Snape's dispassionate voice catalogue his predicament and he would have reacted if he had been able to, but he was incapable of anything except being very, very sick. "Tea, Mr Malfoy, peppermint tea; he will be dehydrated when he is finished."

"Yes, Sir," Harry heard Draco reply, but all he really cared about was the turmoil in his intestine.

Bloody revenge seemed like a very good idea at that moment, just as soon as his stomach let him stand up.

"I shall return to my lab," he heard Snape say.

Harry really didn't want his victim to run away, but there wasn't a lot he could do to stop it. As revenge moved away from him, he realised that he was probably going to get to know the toilet bowl very well.