Ianto stared at Jack contemplatively, and with all the seriousness one could retain when utterly naked playing chess.
"So," he said, apparently having come to some sort of conclusion, "You can't die."
Jack, who was lounging feline-like on the floor next to the chessboard, nodded his head in ascension.
"You come from the future."
"That's right."
"Which means that at some point or another, you travelled through time."
"Yup."
"You were in love with an alien."
"I was." There was a slight pause. "Ianto, if you think that this is going to stop me from winning…"
Ianto smiled wanly, and proceeded to corner Jack's King.
"Check."