This special video was created by the supervising sound editors of A Quiet Place, Ethan Van der Ryn and Erik Aadahl. Though a number of unique techniques, they engage in some Asmr, which stands for Autonomous sensory meridian response. Basically, they make certain sounds with various objects, and it's supposed to trigger various different feelings inside your mind and body. Some people even find Asmr to be arousing.
Asmr videos are a huge Internet trend. Influencers record soothing noises like whispers, soft fabrics, and fingers running through sand.