Or, as I like to call it, the most self-indulgent piece of fanfiction I have ever written and no, I can't bring myself to regret it. I don't like Sebastian but you have to admit, the thought of him partaking in selfcest (of sorts) is pretty damn hot. Or is that just me…?

I wrote this in February but my old laptop broke and I've only just got around to getting all my files from it. This is dedicated to my GAH girls for their endlesss patience – I've been promising this for months now!

I don't own anything apart from the plot (and sorry the summary sucks). Grant Gustin is his own person, and Sebastian Smythe is the intellectual property of Ryan Murphy and Fox. The title is from a Billy Idol song.

Warnings: M/M sex, selfcest (kind of), bad language.

At first Grant Gustin thought it was just paranoia that woke him up in the middle of the night. He had that unmistakeable feeling of a pair of eyes watching him through the darkness At first he tried to dismiss it – it was an unfortunate side-effect of living alone and he knew that it would go away eventually. He buried his head in the pillow and tried to go back to sleep.

Except, unlike those other times, the feeling didn't go away. If anything, it intensified.

After a few minutes, just to give himself peace of mind to drift back off, he propped himself up on the pillow and scanned what should have been an entirely empty room. It took a moment for his eyes to adjust to the darkness and he couldn't see anything out of the ordinary; his dresser, the shapes of scripts on the floor from where he had abandoned them the night before, a tall silhouette at the foot of his bed, his home cinema system – he suppressed a scream as his eyes snapped back to the silhouette. His arm flew out to his bedside table in a desperate search for his lamp. As if the light would deter whoever (or whatever) it was.

He covered his mouth with his hand to muffle a more urgent need to scream as the room was flooded with light and he found himself starting at…well…himself.

No, that wasn't quite right.

As he surveyed the figure; carefully styled hair, an arrogant smirk on their face and the navy blazer with red piping, he realised that he wasn't looking at himself at all. Not really, anyway. He was looking at none other than Sebastian Smythe, the character he played on Glee.

Not that this realisation was exactly comforting.

"Honey, I'm home," the doppelgänger said in Grant…no, Sebastian's voice.

"You're not real," was the only thing Grant managed to choke out, in a pitch he didn't think he was capable of. This had to be a dream. That was it. He was still asleep and was having some insane dream. Okay, the most realistic dream that he had in his twenty-two years of life, but a dream nonetheless.

The mattress sank down as Sebastian (he couldn't believe this) knelt down on the edge of the bed, leaning forward in an obviously seductive manner. Grant wished he would stop looking at him with that dark look in his eyes. He pinched himself hard but the apparition didn't go away.

"Oh I am very, very real," Sebastian drawled.

There was no other explanation. Grant had cracked. He had been working way too hard over the last few weeks and had finally snapped under the pressure of it all. He needed time off and a good night's sleep and maybe some kind of medication. He didn't realise he was hyperventilating until Sebastian started laughing,

"Are you finished freaking out yet?" he asked.

He thought about the breathing exercises Lea kept making him do. Fair enough, they might have been for singing but surely it would come in handy now; in through the nose, out through the mouth, in through the nose, out through the mouth…soon enough, he had calmed down enough to form coherent thought. He had to approach this logically (ha!). Sebastian's presence here was a physically impossibility. Sebastian Smythe was a fictional character. He repeated this in his head like a mantra. If he closed his eyes and counted to ten, Sebastian would be gone.

1, 2…

"That's not going to work-"

3, 4…

"You can keep counting forever but I'm not going to be gone-"

"Shut up, shut up, shut UP!" he said through gritted teeth. 5, 6-

"God, are you really such an idiot?"

Grant gave up on 7. He opened his eyes and started to find Sebastian's face inches from his.

"I'm real, baby, you better get used to it."

"But h-how? W-why? What-?" his next question stuttered to a halt as Sebastian crawled over him. Grant had only ever seen his patented "come-hither" look on the screen. As a straight male, it had taken some imagination to muster up the required lust towards Darren (who teased him no end about it). However, the lust in Sebastian's eyes was unnervingly real. His knees were on either side of Grant's waist and hands on either side of his head. Considering Grant had dragged himself into bed earlier in nothing but a pair of tight boxers that left almost nothing to the imagination, he felt both caged in and extremely exposed.

"Oh, I can't answer any of those questions," Sebastian whispered. He was so close now Grant could feel his breath across his lips – the sensation sent a shiver down his spine that he pretended not to feel, "But I think we should fuck logic and roll with it. I've never kissed myself before, I want to know if I'm as good as people say I am-" for a brief, ridiculous instant Grant couldn't help but think about Chris Colfer's declaration that he had never kissed himself but Chris and everything else was pushed out of his mind when Sebastian pressed his lips against Grant's chapped ones.

It didn't feel so bad. The beginnings of stubble against his face felt strange, and there was none of the softness that came with kissing girls. It didn't gross him out like he thought it might. It just felt…different. Grant wrapped his arms around Sebastian's neck and when he felt a tongue swipe against his bottom lip, he opened his mouth to grant it access. Sebastian's breath tasted like a strange but not entirely unpleasant mix of peppermint and wine. He wrestled Sebastian's tongue with his own but the battle for dominance was over quickly and he let the other man take control. Sebastian tugged the blanket down and the rush of cold air brought goosebumps up on Grant's arms (atleast he was blaming the cold air).

It wasn't until Grant's cock gave an interested twitch that he realised exactly what he was doing. He shoved Sebastian away.

"I can't do this!" he yelped. Sebastian had shed the blazer, shirt and tie in the thirty seconds that they had been making out (if the situation wasn't so strange, Grant might have even been impressed), and he looked unimpressed by the interruption. He raised his eyebrows judgementally and Grant felt himself blush under the scrutiny of the gaze, "You're…well…I…" he couldn't bring himself to say what he wanted to out loud. It was just too insane.

"For being supposedly straight you don't half whine like a faggot," Sebastian breathed in his ear. Grant hated himself for the monster he had created. After all, for the most part Sebastian was just words on a script; it was Grant who brought him to life. He had given him the smirk, the arch of the eyebrow, the "fuck me" eyes…his train of thought was once more depleted as Sebastian swirled his tongue around his earlobe and made him gasp out loud.

Okay, his mind eventually reasoned, this couldn't be real. It just couldn't. He couldn't quite explain what was going on but it wasn't reality. And if it wasn't reality then…he might as well just go with the flow. Right? His body reached this conclusion long before his mind did and Sebastian chuckled as he felt Grant relax underneath him.

"That wasn't so hard now, was it?" he looked at the tent in Grant's boxers (fuck) and laughed, "Unlike other things I could mention."

It seemed that Sebastian knew all his weaknesses. He sucked on the hollow of Grants collarbone, hard enough to add an erotic hint of pain to the pleasure. Grant bit his lip to muffle a moan. It was going to leave a mark…even the thought in his head sounded insane.

Sebastian latched lightly onto his right nipple with his teeth, circling his tongue around the sensitive bud. Grant let out a breathy gasp and arched into the touch, desperate for more contact. Sebastian's hand slid down his side and palmed the bulge that had appeared in Grant's boxers.

When Sebastian was satisfied that Grant was suitably putty in his hands, he trailed wet kisses down the length of his torso. He tugged down the waistband of his boxers, letting Grant's erection spring free. Grant kicked them down the rest of the way. He grabbed Sebastian's hair as the tip of his cock was engulfed in the warm, moist heat of Sebastian's mouth.

Grant Gustin had been with girls…hell, he had been with a lot of girls, but he could quite honestly say that none of them had ever been so skilled with their mouth. Sebastian held his hips to stop them from bucking up as his cheeks hollowed around him. He licked the length of the underside vein, pushing past an apparently non-existent gag reflex. Sebastian looked up at Grant under heavily-lidded eyes, lips swollen erotically and his hair mussed from Grant's grip on it. He lifted his mouth with a vulgar-sounding "pop" and smirked. God, no wonder the fans hated Sebastian so much, even through the haze of want, Grant still wanted to smack him. He tensed when he heard the cap of a lube bottle snap open (where the hell did the lube come from?).

"Don't worry," Sebastian teased. He licked precum from his lips and that shouldn't have been nearly as sexy as it was, "I know what I'm doing."

"Don't worry" ha! That was a laugh. Grant didn't know what was making him more nervous; popping his proverbial gay cherry itself or the fact he was doing it with what was essentially…he couldn't finish that trail of thought but it brought a whole new meaning to the expression "go fuck yourself". He couldn't help but laugh a little, though it ended in a strangled noise as Sebastian penetrated him with one finger. His hips jerked awkwardly as they tried to pull away from the intrusion. Sebastian lowered his head and started sucking him off again – he was pretty sure that mouth was the only thing that was stopping him from losing his erection. This strange obtrusive feeling wasn't particularly arousing. Still, he had been forced to read plenty of graphic fanfiction – thanks to a certain Dominic Barnes – and knew that it supposedly got better. His body had just got used to the feeling of the first finger when Sebastian added the second. He focused more on what Sebastian's mouth was doing rather than his hands; the way his lips slid sinfully up and down his length, his tongue teasing the head-oh. Grant gasped at the feeling of sudden, unexpected pleasure at Sebastian crooked his fingers. It thrummed down his spine. The sensation was intensified at the addition of the third finger and Grant didn't know if he wanted to beg Sebastian to stop, or to beg for more.

"Told you know I know what I'm doing," Sebastian was gone from Grant's lower region, who resented the sudden emptiness more than he would ever admit. Sebastian knelt up. He was now completely naked…when the hell had that happened? He poured some lube onto his palm and rubbed it over his own cock, sighing a little as he did. Grant squeaked in surprise as Sebastian then grabbed his legs and hooked his knees over his shoulders.

The position, with his erection flush against his stomach and Sebastian hard against his ass, made Grant flush with humiliation…which was ridiculous really, it was technically nothing the doppelgänger hadn't seen before. He groaned as Sebastian's cock pushed against his entrance. Grant's face twisted into a grimace as an unpleasant white-hot pain shot up his spine and down his legs. This was much bigger than a couple of fingers, and the stretch was more extreme. He had to clamp his lips together to stop himself telling Sebastian to stop.

"Such a tight little virgin," Sebastian's wrecked voice groaned.

"Will you shut up?" Grant managed to reply, "Fuuuuucck…." His words stuttered as – in a probably deliberate move for telling him to shut up – Sebastian pushed in to the hilt with what Grant thought was unnecessary force. Tears formed at the corner of his eyes but he had already experienced how good it could feel with just three fingers. He wanted this.

God, it scared him how much he wanted this.

Sebastian was still, merciful enough to let Grant get used to this new feeling, though there was a careful expression on his as if he was only just managing stopping himself from fucking Grant right into the mattress. Eventually, Grant jerked his head to let the other man know that it was okay to move. The initial pace was slow and steady; in, withdraw, in, withdraw at a lazy pace.

"Faster," he gasped.

Sebastian was happy to comply. Grant wondered if he looked as debauched as Sebastian did; mouth hanging open as he panted, once perfect hair clinging to his forehead with sweat, pupils blown wide, and a flush from his cheeks down to his chest. Sebastian's nails dug into Grants thighs as he started to pounded more roughly into him. He clung onto the sheets for dear life, as if he would fall off the planet should he let go. Sebastian was brushing against something that felt really good, a tantalising sensation of pleasure but it wasn't quite enough…

Sebastian rotated his hips and… "ohfuckohfuckohfuck…"

There. Right there. Stars burst behind Grant's eyelids and all attempts to stay quiet were thrown out of the window as Sebastian hit his prostate. Those stories he had been forced to read hadn't been exaggerating how it felt. Pleasure, much like pain, shot through him in white hot sparks and it was almost as unbearable. Grant had never been the vocal type but he was moaning unabashedly now, not caring how much he might have been feeding Sebastian's ego. He was pretty sure the words leaving his mouth weren't anything more than gibberish with the occasional curse. He couldn't last long like this. Now the original discomfort had passed, Sebastian was showing no prudence towards fucking Grant's brains out, who was only too happy to go with it. His hands – which he had hardly realised were teasing his nipples – slid down his sweat-slicked torso down to his cock. He started jerking himself off in a syncopated, erratic rhythm. The heat and tension build in his gut and spreading through his shaking muscles. He couldn't keep his eyes opened, he could only focus on how something had to give, it was getting too much-

Before he knew it he was coming completely undone, the blissful numbness of the most intense orgasm he had ever had completely overtaking him. He barely heard Sebastian groan out a string of gibberish of his own, or felt the rather warmth of cum filling him. He could only lie there, heart pounding against his ribcage and panting from the exertion. His skin felt impossibly sensitive to the touch.

Sebastian unhooked his legs from over his shoulders and Grant let them slump uselessly against the bed. He closed his eyes for a brief moment to bask in the warm afterglow of his orgasm…

He didn't remember falling asleep but the next thing he knew, he had woken up completely naked with the sun streaming in from a crack in his curtains. His duvet and underwear were lying unwanted on the floor by the bed. It took him several moments to find his bearings. Slowly and surely the events of the night before replayed in fast-forward through his mind. He stared groggily around, as if half-expecting Sebastian to jump out at him. When this didn't happen, Grant couldn't help but laugh out loud. He ran a relieved hand through his hair. A dream. Of course it had been a dream. What else could it have been? However…he could practically still feel Sebastian's hands and mouth all over him. He grimaced at his sweat-soaked skin and cum drying on his stomach.

Dream or not, it had felt very, very real.

"Crazy," he thought aloud, running his hand absently over his collarbone. He hissed in pain as his fingers brushed against a large, purple lump. A lump on the exact spot Sebastian had been sucking-

"Someone had fun last night."

He sat up abruptly, either from the discovery of a hickey that shouldn't have been there or from the new, frightfully familiar voice, he wasn't sure. His eyes widened as he looked at the two figures standing at the bottom of the bed.

"Let's be honest here," Scott grinned, his arm slung loosely over his twin brother's shoulder, "This isn't the weirdest thing that's happened to you in the last twelve hours."

The End