Everyone has gone home, even Gwen; Jack’s finally managed to persuade her to leave. He was under the impression that Ianto had left too, but apparently he was wrong about that.
“What are you still doing here? Don’t you have somewhere else to be?”
Ianto shrugs. “I thought someone should fix this for you.” He indicates the hand, now in a new containment jar, the fluid bubbling merrily.
“Because it’s obviously important to you. Things that matter to people need to be cared for.” Ianto smiles faintly; Jack has his hand, Ianto has Lisa. Maybe they’re not so different.