After leaving Penny at Amy's, Leonard rushed up to his and Sheldon's apartment.
"Sheldon? Sheldon, where are you?"
The lights were all out, but he could see the dim glow of the night light in Sheldon's bedroom. He walked down the hall and knocked softly on the door.
"Buddy, can I come in?" Leonard called quietly. There was no answer, but he cracked the door open enough to see Sheldon lying face down on the bed. Leonard came closer, cautiously.
"Sheldon, are you all right?" Leonard asked.
Sheldon looked up and Leonard stopped in his tracks. Sheldon's face was twisted in pain.
"Leonard, I'm not feeling well," Sheldon moaned. "My stomach hurts, my head hurts, I can't really think straight. I just don't understand…."
"It's okay, buddy, I'm here. Just tell me about it."
"I feel so helpless," Sheldon leaned up on his elbows and looked at Leonard. "I don't even know what I did wrong, really, and somehow Amy doesn't even want to see me, or talk to me. And I don't know what to do…."
"Penny's over there now with her," Leonard said, trying to reassure his friend. "I think Amy will be able to talk to you once she has some time to settle down."
"Okay," Sheldon said doubtfully. "I hope so."
And then, "Leonard…how do you do it?"
"Do what?"
"Be a genius at relationships," Sheldon said.
Leonard thought he was kidding, but quickly saw that Sheldon was serious.
"What do you mean?"
"Do you remember that night when I told you how well Amy and I did on the relationship scale?" Sheldon started.
"An 8.2, as I recall," Leonard said with a wry smile.
"Afterwards I was saying to Amy that of course we would do well, we were two geniuses, or at least one and half. But she got angry, and said I might be a scientific genius, but I was a relationship moron. She said you were the relationship genius."
"Do you know what she meant?" Leonard asked.
"She said you always know what Penny is feeling, and you always know how to say the right thing or do the right thing. She said I needed to take relationship lessons from you. So can I?"
Leonard was startled. "Gee, I don't know if that's something you can teach."
"Don't be ridiculous," Sheldon scoffed, "if you can do it, it can be taught."
"Gee, thanks," Leonard said; but he realized that Sheldon was serious. "Let me think." He paused for a few moments to collect his thoughts.