The Joker's tongue flicked, and Batman hated him.
If he had to watch it shoot out one more time, he'd…
He held his breath and shifted his eyes away. It was bad enough that he was here again; he'd rather not add to the regret and aggravation by looking at that quirk of a habit -- the one reserved only for him. Clenching his fingers against the wall behind him, he searched for any bit of an edge to cling to.
As if hyper-aware of his torn mouth, the Joker licked. The pink dart swept the scars -- reminding himself he was still grotesque, reminding Batman to keep watching him carefully.
The Joker's lips curved up, and Batman hated him.
They parted and stretched in an odd shape -- neither a smile nor a snarl. There used to be a layer of red paint that came off on everything it touched, even his own teeth. The tongue curled again, swirling much more slowly this time. It pulled him in.
The Joker's mouth slid forward, and Batman hated himself.
The tongue rippled and rolled under him. Liquid heat closed around him and he pushed into it. Though never sure whether it was weakness or wildness driving him past the point of control, moments like this were the only times he didn't dwell on it. He groped out blindly again, found hair, pulled two fistfuls closer.
He canted his hips, slipping deeply into the firm pressure of the Joker's raw lips. He despised how alive he felt, diving off the brink with that maniac. He hated this addiction, hated the Joker, and hated himself even more -- right up until the instant of his climax. At that reckless moment there was only need, a surge, a grunt, and then…nothing.
Just for a moment he found peace, then the hate came rushing back as the Joker swallowed and laughed with the same choking breath. The Joker's grin reverted to its usual mocking line once again, after a final lingering lick to each corner of his mouth. He shifted his shoulders and the buckles of his straitjacket creaked.
Batman slammed the padded white door shut and looked back in through the narrow slit of a window. The Joker stared back -- brooding, defiant, but without a trace of malice. Instead, he merely pinched his tongue between his teeth and stared back at him.
Batman fled in an angry whirl of black cape, loathing the Joker and loathing himself. If only the Joker would hate him in return, perhaps this time could have been the last time.
Maybe next time would be the last time.