They chose David's bed.
It was actually his decision, because he knew the bed. It gave him a substitute of comfort and security. If they had chosen Gustav's bed, he probably wouldn't have been able to trust himself. A big, old-fashioned bed with columns, so romantic and reminiscent of scenes from Gustav's books... Scenes where passion took possession of the hearts and bodies of male characters....
So David slipped into the familiar sheets of the bed where he had already spent the night. It was an ordinary bed, so bizarre erotic fantasies would not come to his mind.