They startled when Remus’s phone buzzed in his pocket. They were standing so close that Sirius felt the vibration against his own thigh, and he acted without thinking. He reached into Remus’s trouser pocket to retrieve the phone for him, his hand dragging slowly against the firm muscles through the thin fabric. Remus’s leg slid closer to Sirius at his touch, easing between his knees, and their twin heartbeats quickened.