Inwardly, Ianto wanted to slap himself for even suggesting a proposition he wasn't entirely prepared for. Too late now though. Whether he joined in or not, it looked like Jack and John were going to shag. And he couldn't exactly let Jack have sex with the other Time Agent and not be there.

He shrugged. "C'est la vie," he muttered. He'd made the offer, now he had to go through with it. It was just sex. He wasn't entirely sure what a threesome entailed, but he was more than positive Jack and John had been in one before. Multiple ones.

He walked over to them, leaning against the bedroom door-frame, expectantly watching them kiss. He had to admit, it was more than a little enthralling.