They may be rather low-tech as medical devices go but Hesogomu Karametoru (Belly Button "Sesame Mixer-Catchers", seriously) were made to help you, the user, patrol the front lines of antibacterial navel warfare.
Maybe you don't care about the dirt, lint and other assorted debris constantly accumulating in your navel. Maybe you're oblivious to the approximately 600 types of bacteria partying 24-7 at Club Umbilicus. Maybe you have an outie.
Regardless, swabbing the decks at the ol' navel base just got easier and pricier as well. A hefty 1,890 yen (about $24) is what you'll pay for a mere 10 specially designed cotton swabs and a tube of organic, dirt-absorbing, plant-based gel... and you WILL pay, now that we've told you what's going on down there, IN there, as you're reading this. Eww