This is certainly more familiar ground. That sound tingles pleasantly down his spine in a contented sort of way, and Levi leaves a few kisses to Erwin's chest and collar bones, snuggling closer. Now, skin on skin and the warmth of it feels soothing, enough that he might doze a little himself. Levi tangles their legs, scratches fondly at a place between Erwin's shoulder blades, and just hums softly in agreement.