Extraneous, maybe, but Héctor does the same. It's grounding. He needs that.

He lifts a brow at the offered cigarette, but takes it, holding it out for a light. He never smoked in life, not really, but he didn't have much against it when it wasn't doing either them a lick of harm. He looks up at the moon too, taking a drag and letting go, before turning back to Sherlock.

"You want to talk about it?"