Only ever with Lucien if Nate had it his way and the same for Lucien. Nobody else would touch his boy while he was able to stop it.
Nate took the invitation for what it was and bit Lucien's neck, sucking and licking until there was a red mark which would linger. Lucien would see it in the morning and remember everything they'd done, as would Nate. He'd found that seeing marks on Lucien's body which he'd put there previously were quite a big turn on for him. Just like seeing the ring on his finger was, Nate was possessive. But with Lucien he was allowed to be. "Never" he tightened his hold on his love, "Always with you. Always love you" He continued pounding into Lucien, feeling that intense feeling approaching and closed his eyes willing himself to last longer.