Mei Changsu does his best to avoid entering the tunnel between his house and Jingyan's; the braziers set up in the small subterranean sitting area can't be kept burning indefinitely, and the cold goes straight to his bones. Still, he keeps some important documents here. Sometimes going underground can't be helped. Everyone else in his household is busy, and although he knows they'll all scold him for not paying attention to his limits, it's just a quick trip. Sometimes he wants things to still be as simple as they seemed when he was young. He needs a book, and he will retrieve it himself. It's not so large a task. Doctor Yan doesn't even have to know.
Something seems strange about the tunnel when he enters it. When he lights a lamp, the glow diffuses strangely. Has someone else been inside? He'll have to ask Jingyan and Meng da-ge if it was them. Even the existence of this tunnel would be damning if anyone else were to find it. He takes a few cautious steps forward, ready to shout for Fei Liu through the open door.
One more step, his footfalls echoing on the cobblestone floor, and then... he emerges into the light, somewhere else.