A/N: This one-shot is presented in friendship and sympathy to chasingriver, who spent some nasty days in Migraine Town recently. Even Sherlock gets them, my dear, but too bad we don't have access to his cure. Warning for Holmescest.

As the sun set, Sherlock said goodbye to the hours of agony with a shaky sigh of relief.

Mycroft's cool fingers stroked his alabaster brow. "Better now?"

"Mmm."

"Need anything else?"

Sherlock's eyes were feverishly bright. No longer caged by pain, other parts of his body stirred to life.

"Yes," he said throatily. "I do. Quite badly."

Sherlock had known he was in trouble the moment he opened his eyes that morning. Shimmering pinpricks of aura competed with the sunlight flooding into the room, until the brilliance seared his vision and he grimaced, knowing what came next and dreading it.

The inaugural throb over his left eye hit with such force that he cried out, feeling as if an unseen enemy had punched him there. His head actually snapped to one side and hit the pillow with a dull thud. Then a vicious pounding erupted in his forehead, followed by a cold sweat and hot nausea.

After twenty minutes of trying –and failing- to make the pain go away via relaxation exercises, he got up to close the blinds. Then, shielding his eyes from the intolerable daylight, he stumbled to the kitchen for ice and piping hot tea, which worked better on his migraines than paracetamol. The ice pack provided marginal relief, but minutes after forcing himself to swallow half a cup, Sherlock vomited up the tea.

He remained on the chilly bathroom floor for awhile, palms pressed to his temples and tears of distress coursing down his face. The medicine cabinet was stocked with painkillers, mostly for John's shoulder, but Sherlock's body was so drug-resistant after years of substance abuse that taking anything was useless. He'd overdose before a significant dent was made in the pain.

Sherlock finally staggered to his feet, despair yielding to anger. He grabbed fistfuls of his hair and tugged, cursing, hating his head for hurting so badly. He'd read in a medical journal that people with migraines often hit their head against a wall, and understood why: it wasn't masochism at work, but a sick yearning to force his body past the point where it could keep signaling pain.

John was away at Brighton for the weekend and Mrs. Hudson's motherly frenzy would have made things worse, so Sherlock, his traditional defenses disabled by suffering, texted Mycroft. And Mycroft had come.

As the hours passed in dimness and hushed silence, Sherlock decided that he hated his older brother a little less. Mycroft had massaged his scalp (finding the pressure points with remarkable accuracy), changed the ice in his pack every hour, emptied the bin at his bedside when he vomited two more times, and even helped him brush his teeth afterward to chase away the bitter taste of bile. When Sherlock's pajamas became so sweat-soaked that they clung wetly to his bony frame, Mycroft stripped them off with impersonal efficiency, scrubbed him down with a damp towel, and pulled soft flannel bottoms over his hips.

Now evening approached, and the throbbing slowly ebbed with the fading daylight. When his head was finally silent, the natural impulses that had lain dormant all day sprang to full, demanding life. His thoughts, no longer foggy with pain, ran rampant like freed rats. His stomach growled, craving Chinese or pasta or something else ridiculously rich and heavy. His cock swelled with blood and pressed insistently against his flat belly, demanding relief. Had he been hard all day? He hadn't been capable of noticing.

Until now.

After Mycroft's query ("Better now?") and his affirmative response ("Mmm."), Sherlock's erection twitched so aggressively that his long fingers moved toward the waistband of his pajama bottoms. He closed his eyes, expecting Mycroft to understand and give him some privacy. Therefore, when a warm hand stopped his, he froze.

"Let me," his older brother said in those soft, seductive tones. "I know what to do."

Sherlock nodded and let his hand fall to the mattress. Mycroft did know. It had been ages since they'd done this, but time could never weaken their intimate knowledge of each other's bodies. No matter how much they feuded, something hot and unquenchable had been aroused that night fifteen years ago, when Sherlock had been recovering from pneumonia and Mycroft rubbed soothing ointment onto his bare chest. One accidental finger brush against his nipple led to groans and delicious pain and oh, please, deeper….

He felt the mattress dip as Mycroft sat on its edge. One broad hand threaded through his dark, matted curls, just before warm lips that tasted of tea and expensive breath mints pressed against his. Keeping his eyes shut, Sherlock shuddered with anticipation as his brother's tongue swept all over the inside of his mouth. When he felt fingers slide down his belly, toward his cock, he whimpered, "Please."

Mycroft stroked him slowly, sensually. Moaning in pleasure, Sherlock thrust his hips urgently upward, into that masterful hold, which responded by moving faster and gripping tighter, his own pre-come slicking the way.

"Oh," he panted. "F-fuck."

"That's so good," Mycroft encouraged him over the wet slapslapslap of slick palm against hard flesh. "Come for me, Sherlock. You deserve a release."

As he stampeded toward orgasm, Sherlock's hips snapped up and down with mounting force, causing the mattress springs to creak wildly. Then his aching balls tightened, the thrumming in his cock escalated into violent pulsations, and he was coming, coming in messy white globs all over Mycroft's hand, all the while shouting himself hoarse.

Mycroft slid an arm under his shoulders and drew him close as he writhed through the post-climax shivers. The hand on his cock turned gentle, massaging his softening flesh until he stilled, body flooded with freshly released hormones.

"Okay?" the elder Holmes whispered.

"Yes," Sherlock whispered.

He closed his eyes, unable to keep them open, and grasped Mycroft's hand. He squeezed it and tried to say "Thank you", but his lips only formed the words before he was fast asleep, comfortable and sated and, most precious of all, pain-free.