He watches the gleaming light drift in with no real concern; it is drawn to Ciri by means of the seeking enchantment laid on it, he supposes. But as it dissipates into her and she draws breath, as she holds on to Geralt, Lan Wangji staggers with the weight of his shock and puts out a hand to brace himself against the wall - in part for support, and in part to keep himself from rushing forward.

Not dead, or not truly; only depleted somehow, her spirit restored with the spark of power from the spell-sphere. His jaw firms. If it is spiritual energy she needs, that he can provide.