Set after Jack came back from traveling with The Doctor. What if something bad had happened to Ianto while Jack was gone?What happened to Ianto I'll leave up to you.
"I'm sorry Ianto,"Jack said."If I had known,if I had been there-"
"There was no way you could have known and nothing you could have done,"Ianto said and it was the truth. At first Ianto had been mad at Jack but then he realized that Jack being there wouldn't have changed anything and he could hardly blame Jack for leaving,it had been a chance for Jack to possibly cure his immortality and he had waited several centuries for The Doctor.
And Ianto expected Jack to never mention it again after that. He hadn't expected Jack to ask him if he needed to talk about what happened to him and he never expected Jack to ask him out,especially not in the broken state Ianto was in now. He could hardly sleep or work.
But I can still shag him, I suppose that's what matters to Jack,Ianto thought but he dated Jack anyway.
And when he woke up from the violent nightmares the experience had given him, he hadn't expected Jack to still be there or for Jack to hold and comfort him but Jack was sleeping over so often that he might of well have moved in. Ianto wouldn't put moving in without telling him past Jack.
"I love you,"Jack said one night surprising Ianto. And Jack hadn't expected Ianto to pull out of his embrace,get dressed and walk out into the street but Ianto did do that. Jack guessed that this was Ianto's way of saying I don't love you but what he knew was that Ianto was in no condition to wandering around at night so he followed after him.
Expected is repeated so much here because I think it fits the theme of the drabble.