It's a massage for your brain, and thousands of Australians are tuning in, hoping for a better night sleep.
ASMR, or Autonomic Sensory Meridian Response is one of the fastest growing trends on the internet.
Sometimes called "brain massage", the term ASMR was coined in 2010 for the tingling, pleasurable sensation that ASMR practitioners or "ASMRtists" can induce in a listener's body through sound triggers like whispering, tapping, and brushing, reports news.com.au.
ASMR is also induced with scenarios of nurturing, non-sexual "personal care", so the ASMRTist may talk directly to camera in role-plays of haircuts and doctor visits.
Narration is whispered, paper is scrunched, water is poured and microphones are brushed and tapped with different objects.
Meanwhile, devotees (sometimes called "tingleheads") slump smiling in their headphones, bones turned to jelly, and ASMRtists rake in the big bucks.
It sounds truly nutty, but there is an undeniable physiological response being induced.
While not all people respond to ASMR, those that do describe sensations of tingling that originate in the back of the scalp and radiate down the spine, sometimes into the shoulders, arms and legs.
People turn to ASMR for help with insomnia and anxiety and to induce a state of relaxation.
"It feels like starbursts in my head," comments Andrea on one YouTube video. "My body loosens immensely, like after drinking wine," says Nyx.
"The physical sensation ends almost immediately with the stimulus," says Jean, "but the euphoria and peaceful calm can last for several minutes afterwards. ASMR can really relax me for hours."
ASMR is thought to be related to synaesthesia (which can cause people to experience otherwise unrelated secondary sensations to sensory stimuli) and to "chills", or "frisson", the name given to the physical sensation sometimes experienced when listening to music.
The popularity of ASMR is undeniable. There are 127,000 subscribers to the ASMR sub-Reddit, 19 million results on a Google search and more than 7 million results on YouTube.
Many people use the videos to sleep, with most searches occurring at about 10.30pm, across different time zones, according to Google Trends.
So why does the ASMR response occur? Is it related to dopamine? To serotonin? To oxytocin? Is it some lizard-brain response to nurturing and calming sounds and behaviours that replicate infancy?
Are ASNR triggers activating some biological bonding mechanism? All these theories are in play, but the science is not yet in.
Dartmouth research examining the neurobiology of the reward system by using fMRI analysis is pending, and there have been, to date, six peer-reviewed papers including one that examined the personality types of those who experience ASMR.
It is charmingly strange, this is certain. ASMR video titles include: "Little Bat Yawning and Flapping It's Wings", "Ear Massage with Reading Classic Slovak Short Story" and "Eating a Whole Rotisserie Chicken".
One of the most beloved tropes of the ASMR scene is the painter Bob Ross, whose 80s cult-classic TV show, which featured his distinctive gentle voice and the notably loud scraping of his paintbrush on canvas, has an undeniably soporific quality.
W Magazine recently posted a celebrity ASMR series, in which Cara Delevigne swore quietly, and Kate Hudson fondled sequins and snipped fabrics with a giant pair of scissors.
Brands too, are taking note of the commercial potential of ASMR.
It's been used to sell beer and chocolate, and recently KFC recently hired actor George Hamilton to whisper about pocket squares and crunch on fried chicken, conflating in listeners minds the "comfort" of fried food and relaxation.
At least, this was the aim of the marketing wonks at KFC. Whether it sold more chicken, it's hard to know.
ASMR is definitely bizarre. But also, perhaps, brilliant: A mingling of technology and neuroscience, where the freedom of YouTube - to be a citizen filmmaker, to build communities, to do nutty, experimental things - has ended up creating a product way too odd to have gained traction in the traditional business world.
ASMR may truly help people suffering insomnia and anxiety, and it may have other implications too, yet to evolve. It's a quintessentially YouTube phenomenon; *whispers* Watch this space.