The last time is on Marcus' chesterfield, amid the cluttered charmed documents they never talk about. He whispers fervent words against Marcus' skin, and Marcus pretends not to hear them.
He asks, how do you say goodbye today to someone you could be killing tomorrow? Marcus says, you don't, and Oliver has to get up, because Marcus is crushing the breath from his lungs.
In the morning, Oliver will take everything with him, and pretend he never had anything to hide.
Marcus never told him anything, anyway.