Mycroft/Irene
"No need to tell me the details," Mycroft responded, haughtily. "My imagination can fill in the blanks." Not that he was insulting Irene per se, or that he was disturbed by sex. Mycroft simply felt it wan't necessary.
"My insiders gave me a report," Mycroft confessed to spying on their meeting whilst casually flipping ash from his cigarette into a tray, "But I wanted to see if you'd tell me, directly." Would she be willing to speak freely about what she said to Sherlock?
As a child, Mycroft had a collection of Superman comic books, but he'd never tell Irene that. "She's not Superman, or his cousin Supergirl, but she's from the same planet. Evidently they know one another, and if our records are correct, there was a big to-do between them at some point." To put it lightly. "But she possesses the same power set at them, including flight, super human strength and yes, x-ray vision." He took a drag off his cigarette and added, "If you mean to suggest that she's employed as something other than my health trainer, then yes... your assumption is correct."