The look of confusion on Louis' face is an unavoidable by product of trying to recalibrate from Daniel's sudden appearance in the midst of a moment where Louis' entire thought process was struggling through the overwhelming, familiar experience of desiring Lestat.

It is not helped by the still incongruous suggestion that Louis texts him.

So maybe Louis can be forgiven for answering, "What?" as he buffers through to steadier, cooler composure to correct himself and supplement, "Yes, I'll text you."

And then swivel his focus as he straightens, collects himself to call back, "Where have you been?" towards Daniel's room.

Nailed it.