Mewtwo felt the spirits of the trillion restless dead that perpetually patrolled the psionically unhallowed ruins of Cinnabar Island as he himself paced the halls of his mansion, except he didn't literally pace because he hovered several centimeters (or slightly fewer inches) above the ground. Every time a moaning spectre screamed its silent gasps of horror, Mewtwo recalled the exact circumstances under which he had killed it. Killed to gauge the limits of his power during his first, ignominous stay at CInnabar Mansion. Annihilated incidentally as a byproduct of a psychic attack directed elsewhere. Romantic rivals disposed. Celadon High cheerleaders he'd discovered had tormented Erika. Mewtwo's highly-developed sense of decorum prevented him from giggling to himself each time he fondly reminisced.
Mewtwo reached the extremely heavy door wrought of Aggron carapace behind which Erika's chambers were. He decided between lifting the door psychically with his mind and just phasing through it immaterially, but before he could make up his mind Erika came out into the hallway anyway, where Mewtwo was, and talked to him.
"So, champ, I take it we have a visitor?" she asked slyly (i.e. by winking seductively (which she always was)).
Mewtwo nodded sagely and then replied "Yes," confirming her inquiry.
Erika wriggled sensuously within her sexy kimono, which had slits going up the sides to show off her smoking (wink) hot body, and which was patterned with subtle mathematical patterns based on the fractal rhythmic recurrences of their boning sessions. She also had a thong, but only Mewtwo could tell by now. Shadow would only be able to tell later, after most of her kimono was no longer properly covering her body. Shadow is still in this story.
As one might expect, biology worked its way through Mewtwo's loins and engorged his trouser Arbok (a metaphor which only truly applied on rare occasions on which Mewtwo elected to wear trousers; he was capable of style when situations merited). Erika playfully batted it about with her paper fan, which she was carrying, and said
"Not yet, fun-bun. Guests first." Then winked.
The two of them glided (because Mewtwo had enhanced Erika's latent psionic abilities and now she could hover too when she wanted) down the hallway, to the forest where Shadow was. If a camera had been positioned at the doorway through which Erika had originally exited, it would have picked up the seductive shimmering of her buttocks beneath her kimono as she walked away; a similarly situated microphone would have captured (gradually trailing off) their charming and amusing banter as they drifted out of audio pickup range.
Shadow's Chaos Sense, which allowed him to sense chaos, alerted him to impending chaos. For a second he was on maximum alertness, ready to deal with any threat. Then he remembered where he was: Mewtwo's extraordinarily lavish and detail-rich mansion. He looked around and tried to see where Mewtwo was. Then he walked around, in case Mewtwo wasn't visible from his exact current location.
After fifty seconds of walking, Shadow came into view of Mewtwo. But it wasn't Mewtwo that caught his attention. Yowza, he thought to himself, surprisedly and arousedly, with regards to Erika, who was with Mewtwo. The two of them smiled beatifically at Shadow, suggesting subtly through their body language what else their mouths could do other than smile. They could frown, and they could speak. But what utterances would flow forth later this eve(ning)?
"Hello, Erika," said Shadow. "I like your kimono." He realized he wasn't wearing any clothes, because he was a hedgehog. Reflexively his hands twitched to cover his genitals, since even at this early juncture he was aroused enough by Erika's petite yet shapely and probably firm breasts that his tallywacker had emerged from its abdominal sheath.
"Look at this square," chuckled Erika. With one smooth motion, she undid the various buckles and straps that held her kimono on and stepped forward revealing her body except the part that was under her thong (as foreshadowed earlier). Mewtwo could have used his X-ray vision to see under it but chose not to. "What are you hiding?"
"Nothing, I guess," said Shadow. He spread his arms wide, to demonstrate vulnerability and perhaps in anticipation of embrace. "As you can see, you have greatly aroused me." He felt very suave, because he was.
Erika pushed hard against his chest, sitting him down. "Let's get 'jiggy' with it." She began to pull off one of Shadow's gloves, but he placed his other hand on hers. Silently she knew they would remain on. The fabric was still luxuriantly smooth, even moreso than velour.
She grabbed his todger in a double-handed embrace. Her eyebrows danced the lambada (the forbidden dance!) across her brow. As her fingers played across Shadow's turgid shaft, Shadow moaned at a peculiarly high pitch. It was indeed more of a crooning than a moaning.
Mewtwo gazed stoically on.
Shadow splayed his legs wide and inviting. Erika dipped her head down, like a porpoise returning to the sea after surfacing. As quickly as a boa constrictor's couldn't, her mouth was entirely enveloping his boner. Shadow arched his back in pleasure. His shoulders tensed, and as his body locked up only to be jolted with muscular spasms. Erika was also experiencing physical symptoms of sexual arousal.
Suddenly Mewtwo was immediately behind Erika. Rather than hovering stationary, his flight path experienced slight perturbations, up and down, side to side, in synchronicitous accordance with the patterns traced in air by Erika's buttocks.
"Let's crank some tunes," he said, and suddenly throughout the forest pumped the energizing and arousing strains of "Make Glorious the Embrace of Saturn" by Anaal Nathrakh. As Erika started to headbang with Shadow's wiener still deep in her throat, the strange new resonances of motion inspired new waves of arousal in Shadow. A million times stronger than ever before had he, he came.
Flushed with shame, he said "I'm sorry, I didn't want to disappoint you. Thank you for inviting me into your home."
Mewtwo and Erika laughed, with only the slightest edge of condescending cruelty.
"Don't you realize," said Mewtwo, "That I can psychically replenish your supply of semen?"
Suddenly Shadow realized that he was in for a very long night indeed.