It was the most overwhelming feeling, knowing what was in Sirius' mind, obtaining a mental and physical connection so complete that they were truly one. Desire and lust rolled powerful from his mind through his body and back in his mind. The faster Sirius moved, the closer they both got and the harder it was to separate the origin of the sensation.
When Sirius change the angle, the pleasure enveloped him so thoroughly that he almost closed his eyes, but he couldn't not without breaking the spell and the connection. He fought to keep his control over his body and his magic, but knowing that he wouldn't hold on for long, his closed his fingers around Sirius' cock, adding to the layers of sensations that they were both experiencing.
Come for me. He wasn't sure if he said it aloud or in Sirius' mind, but it didn't matter, not when they could feel so much, too much, and soon James surrendered to what his mind and body wanted, coming buried deep inside Sirius.