Oh, Xianxian.

The hair at the nape of his neck stirs at the ghost of a ghost of a presence, invoked by his earlier desperate thoughts and her brother's own quiet words - and before that, by a ritual at the water's edge. He will have to play Inquiry tomorrow, just in case, but not now.

Now, memory is more important; the memory of Jiang Yanli standing in front of him in the Unclean Realm, gentle and kind and with the strength of bright steel.

Second Young Master Lan. I need to ask you something.

And then again, later, sitting at the bedside where Wei Ying lay unconscious while he himself played guqin, day after day, the two of them united in their determination and the quiet understanding between them.

I promise you, he tells her now, in the silence of his mind, the same words he had spoken to her then. I will do everything I can.

For an instant, he thinks he can feel a breath of air pass through the otherwise still room, drifting lightly over Wei Ying's hair before it fades and is gone.

Lan Wangji closes his eyes, and draws a slow, careful breath of his own.

"Then when you do," he says. "When you must. I will be here when you come back. Like this."

Equally quiet, and very certain.