the meaning of the ritual (слэш)

“Lan Zhan… wants to bed me?”
The hand on his chest is shaking, slightly. “Mn.”
“Oh,” Wei Wuxian breaths out.
There’s something— something powerful, about that. Lan Wangji wants to bed him. Lan Wangji wants to sleep with him. Lan Wangji wants to touch him, and kiss him. The immovable, implacable Second Master of Lan, with a face and principles both carved from jade, wants him.
“Is this a fantasy of yours?” Wei Wuxian asks. “Forcing all the demonic energy out of me with your—”
Lan Wangji claps a hand over his mouth. “Silence, now.”