They'd always resisted this, the both of them. Thor because of their shared blood, and Loki because if Thor had everything else, he wasn't about to grant him this, too. Nevermind if denying it to Thor meant denying it to himself as well.
But now, there was no true relation between them, and as for the rest...Thor had so little remaining, and if he had the throne along with the ashes, well. Loki had already had his taste of ruling, and had found it did not suit.
Still, even if there were no longer any reason not to, and even if this had been coming for centuries, coming ever since that summer when they'd been boys together and discovered the heat that rose between them at the slightest unintended brush of skin—still, every caress felt slightly wrong, and every kiss slightly off, until Thor spoke the lie:
"Brother," he said, lips and breath and a scratch of beard against Loki's neck, and the rest of him hot and thick between Loki's thighs. Loki had begun to think he didn't want any of him after all, but then Thor repeated it: "Brother..."
"Yes," Loki said, and urged him on.