Ianto can tell when John has deemed a conversation to be over, and that is decidedly a sign. He hums softly, deciding that it'd be better to save the rest of the food he's been picking at for if and when they might actually need it, and setting it aside.

"Yeah, alright. But wake me up, yeah?" He glances up at the other man, frowning at him slightly as he does, trying to get a good idea of how he's doing and coming up short. "You're going to need to get some sleep too. I can take second shift." He pats the pocket of his bag. "Should anything go awry, you may rest well and remember I'm armed and dangerous."