Mycroft wasn't sure he'd heard correctly. "Show you?" he echoed.

"Yes, show me. Perhaps I'm doing it wrong. I was going to watch a video, but it's not the same as someone coaching me through it." His white hand snaked off of his lap and gripped Mycroft's knee. "It's an irregular request, I know, but I don't know who else to ask."

The elder Holmes exhaled and mopped his sweating face with his silk handkerchief. "Sherlock, that's, well, that's just not something brothers do in front of each other."

"You did it when I was nine."

"I didn't exactly send you an invite!"

Sherlock leaned in closer. "Please."

His younger brother looked so haunted and anxious that Mycroft didn't have the heart to scold or protest further. Instead, his mind detached, as it had been conditioned to do when under severe duress of any kind: Mummy's concerns about his weight, whips and clubs applied to his body by professional interrogators, Sherlock's request for a wanking lesson. He inhaled through his nose, processed the smells- leather, cologne, sweat- and searched his own hard drive of a brain for data.

Male inability to ejaculate…. Searching….

Going through archive from MI6 days…

Locate folder titled Profiling Human Sexuality

Result found.

Anorgasmic Anejaculation – inability to reach orgasm while awake, either via masturbation or intercourse. Nocturnal emissions may still occur. Sometimes due to psychological inhibitions. Some subjects merely require a high amount of stimulation before they can climax and do not get this stimulation during intercourse or masturbation.

"Here." Sherlock shrugged his coat off and unfastened his trousers. Then he slid his belt through the loops and tossed it to the Persian carpet. "I'll show you how I do it. Watch."

Mycroft's eyes snapped open.

Oh, dear God. If Mummy calls right now to wish a Merry Christmas, the insanity will be complete.

Sherlock lifted his arse off the leather sofa long enough to slide his dark trousers and boxers down to his knees. He was half-hard already: his impressive length bobbed as he shifted and leaned back against the cushions. Closing his eyes and running his tongue quickly over his dry lips, Sherlock began to stroke himself from root to tip.

During the thickening silence that ensued, Mycroft watched and Sherlock demonstrated. At first there were no sounds except the glide of palm against slick flesh. Then the younger man began to moan faintly. His slim white hips rose to fuck his fist more forcefully. Precum first appeared as a tiny bead at the tip of his cockhead, but was soon trickling steadily out.

"Talk to me, Sherlock," Mycroft said hoarsely. His own cock was swelling in his expensive trousers. He'd never been, and was sure he still wasn't, attracted to his own brother, but the sight and smell of a fully aroused male sent the blood rushing to his own nether region. "Tell me what you're thinking of."

"John," Sherlock choked. "His face. His eyes. His body. I want it pressing against me, fucking me into his mattress, making my body and my entire soul his alone…."

Mycroft shifted closer. "What's he doing to you right now?"

Sherlock's closed lids flickered. "He's stroking me. Feels so fucking good, brother." His bare arse creaked noisily on the leather seat.

"Oh, God," Mycroft whispered. He unbuttoned his suit jacket, shrugged it off, and loosened his tie. His cock was now pushing aggressively against his zip, but he planted his hands firmly on his knees, determined not to lose control. It was difficult though. Sherlock looked so beautiful when aroused. His pale cheeks flushed, his soft pink lips parted, and his rich dark curls glided over the leather cushions….

"Ohhhh," Sherlock moaned. His other hand descended to his balls, which he cupped and fondled. His thighs widened. "Almost there. Almost… maybe this is working…."

His stroking became more frantic and his eyes opened, their gaze fixed firmly on the hand-painted ceiling mural. He rolled his head from side to side and increased the ferocity of his hand movements.

It was then that Mycroft noticed a change. Sherlock's blissed-out expression became taut with desperation and he arched his back so tightly that bones and muscles creaked in protest. Then he roared, a ripping sound loaded with disappointment and fury, and collapsed against the cushions again. He let go of his still-rigid prick and hid his face in his hands.

Mycroft leaned forward. "Sherlock ?"

"I can't come," Sherlock hissed. "I thought maybe with someone watching I could finally do it, but I CAN'T."

One of his hands formed a fist and punched his trembling thighs, leaving a red mark that would bruise later. The pain made him hiss, and he poised for another blow, clearly intent on punishing himself further. Mycroft reached forward and caught him by the wrist.

"You're not defective, but you do need help, little brother," he said huskily. "Take off your clothes and lie down. I'm going to fix this."