He tips his head to the side to allow the other man better access to his neck. This is -- nice. Better than nice, Ianto's not quite sure how or why John has started it now when they were supposed to be going to bed, but he'll take it.

"Research mission," he murmurs, sliding his hand up the line of John's torso to trace his fingers in idle patterns across the line of his chest. They may have been cool to start but John really is warm, and Ianto's hands are no doubt warming from the touch as well. "I might have known."

Ianto might be tired but the presence of John straddling his lap is doing a lot to keep that at bay. His heart feels like it's pounding a mile a minute in his chest as he slides his other hand up to tangle in John's hair. Pulling at it slightly, although certainly not to tug him away. "It may take me some time," he replies. "To be that thorough."