Yuan Chen woke at three in the morning on his third day in Zurich. The hotel curtains were so thick that not a sliver of light came through.
He instinctively reached toward the other side of the bed, only to touch cold silk sheets.
London was eight hours behind City A, while Zurich was seven hours behind.
At this hour, Shen Yi should have just finished his afternoon work. Perhaps he was drinking his third cup of coffee that day, if he hadn't forgotten while busy looking after the sick Shi An.
His phone screen lit up in the darkness, showing an unread message from two hours earlier.
Yuan Chen opened it. Shen Yi had sent a photo: Shi An had fallen asleep on the study rug, an open picture book tucked beneath his cheek, with a half-finished cup of coffee nearby. The caption was simple: "He insisted on waiting here for your video call, but he couldn't stay awake."
Yuan Chen stared at the photo for a long time.
He could tell how tired Shen Yi was, even though Shen Yi himself wasn't in the picture. The hand holding the coffee cup had slightly pale knuckles, stiff from long hours of work.
He started a video call. It rang five times before Shen Yi answered. The screen wobbled a few times, then revealed his slightly sleepy face.
Behind him was their study at home, its lights dimmed low.
"Did I wake you?" Yuan Chen kept his voice very soft.
"No, I was just dealing with emails." Shen Yi rubbed between his brows and turned the camera to one side. "Look, your little supervisor is still here."
Shi An smacked his lips in his sleep, his little hand unconsciously clutching the hem of Shen Yi's trousers.
Watching them, Yuan Chen