Ianto didn't fail to notice that almost immediately after Sulu'd allowed himself to be even the slightest bit cynical, he'd reined it in and was back to being positive again. He wasn't sure if that was for his sake, or whether that was just something that Sulu did all the time, but he was grateful for it. Really, there were a lot of things that could go wrong for either of them, and viruses were the least of their worries. At least viruses reverted themselves eventually, right? Space bears or Weevils, on the other hand... His hand stilled in Sulu's hair.

"Come hell or high water, huh?" Ianto repeated, mulling it over. Ianto just simply wasn't as optimistic as Sulu, and so he couldn't say for certain that they would be able to stop everything that got in between the two of them, everything that kept one from another, but. He was more than willing to try. "Well. I'm not sure that there's much I can do, but. I'm try to keep up my end of the deal as well. Come hell or high water, as you say," he said, with a small smile.