Rotger's going to leave.
Olaf knows this, the same way he knows that he's a Drix, that he'll never pass a navigation exam without caesar paying his studies, that seven young fähnrichs from the North weren't nearly compensation enough for being stuck with Bermesser as Oberfähnrich zur See. It's as simple as that.
Rotger leaves, every time. And that seems stupidly obvious, because of course Rotger leaves; they can't hang around in an empty classroom or the sail shed forever. But it's not like that. Rotger leaves, and there's no doubt in Olaf's mind that every time he walks out, he intends it to be the last. Intends to go back to Almeida, and to stay with Almeida, and there's nothing Olaf can do or say about it. And every time, more days pass before Rotger approaches him again, and one of these days, he won't come back.
And really, he should have known better. Rotger's a Marikiare, and Marikiare hate Drixes, and that's another one of those things that Olaf knows. And if he forgets, his friends are more than willing to remind him.
NC-17"Fuck him if you have to," Schneetal tells him, one night when everyone else in their dorm is asleep. Schneetal is even more bitter than usual on the subject of Marikiare this year, for reasons he hasn't shared and Olaf hasn't asked about. "But for Creator's sake, remember that he's only slumming. He won't forget it, no matter what he says."
Rotger doesn't say, actually; he never says much at all, beyond the sort of thing you can't help but say when you're being fucked against a wall. And Olaf never forgets, even when he tries to pretend that Rotger came back because he missed Olaf, instead of what they both know is true: Rotger only comes back because Almeida doesn't like to play rough, and he knows Olaf will.
This time, though, he's seized by some urge to mark Rotger, and he leaves a pattern of bites on Rotger's neck and shoulder. Rotger might leave, he thinks, but at least Almeida will know where he was.
Later, when Rotger's hand is on the door, Olaf stops him. "Why?" He can't say anything else, and it's too much, he thinks, to expect Rotger to understand him.
But for once, he seems to, because he turns around and looks at Olaf for a long time before saying, "He loves me."
There are ashes on his tongue, dust in his mouth, and whatever he might want to say to Rotger, whatever lies he might think to tell to keep him here - it had all evaporated, and the only thing left is, "Well, if that's what you want."
"It is."
Rotger waits for a moment, as though expecting Olaf to say something else. Then he shrugs and opens the door. "I do know basic healing methods," he calls over his shoulder. "No one will ever see those bruises."
And then he's gone, as simple as that.