(A/N: Takes place after Private Lives and Public Drama, chapter 14 but before chapter 15 begins)
Friends with benefits. That was probably the best way to describe Mycroft's relationship with Ian Richards and Rachel Jones. He had no desire for romantic relationships, felt no romantic attraction to them—anything more than friendship was purely physical.
And now, he had a choice to make. Sherlock had left for Baker Street earlier in the afternoon, and he had started to complain of morphine withdrawal. Rachel was a doctor; she'd looked after Sherlock during the seemingly endless three weeks that he'd spent at the Holmes estate while John—or rather Jack—had swanned off to America, leaving his already deeply troubled flatmate in trouble. But perpetual sedation had seemed necessary, and Mycroft had reluctantly allowed it.
He had concerns for Sherlock's addictive personality. Putting him on morphine, which is chemically indistinguishable from heroin the minute it crosses the blood-brain barrier, was not his first choice. He knew Sherlock had used it before, medicinally, when he was having painful sensory overloads, but was never actually addicted. But Rachel had ruined that. She'd been made aware of Sherlock's tendency toward addiction, and of course she knew the dangers of perpetual morphine dosing, but as no other sedative had any sort of effect, she had insisted. Now, Sherlock was in pain from the withdrawals and Mycroft had to do something, even if it would mean putting his friend's job at risk.
He placed his hand on her shoulder. "He's suffering withdrawals," he said simply, and she sighed, uncomfortable. "He's entirely addicted."
Rachel sat, legs weakened by the realization of what she'd done. "God," she whispered. "I'm sorry." It wasn't a plea for forgiveness, it was a deep apology and expression of sympathy. She put her face in her hands. She was a trauma doctor, she'd seen people come in with heroin addictions, and she fully understood what she'd done. "I had a plan," she whispered. "I was going to wean him off it when John came back, a little at a time so he wouldn't suffer like this, but John's his official doctor, and I can't overrule him." John had taken him home almost instantly after his return, after Sherlock's suicide attempt, and she hadn't had time to take him off the morphine slowly, properly.
"Yes," Mycroft said, concerned. He'd begun to question John's abilities as a doctor of late, given both John's mental health and the way he'd made Sherlock go cold turkey after his recent relapse into cocaine addiction, not to mention the fact that he hadn't practiced medicine in nearly a year. But John was the only person Sherlock trusted to look after him, so Mycroft hesitated to insist he be recertified. "I will have a talk with him about that. As I must with you," he said, voice turning stern. Rachel's eyes started watering, knowing how much a stickler for the rules Mycroft was, and knowing what was coming. "I will have to report this incident. I'm sorry." He squeezed her shoulder gently and picked up his phone, making a phone call that some would call callous, reporting Rachel for potential misconduct, leading a patient to addiction, knowing she would have her license to practice medicine suspended if not revoked until an inquiry into the incident could be completed.