A Mootix is a petpetpet that looks like a flea; petpetpets are little bugs that go on your petpet. One of these little guys costs ~600-800k. They’re actually rather popular around Neopia! There are Mootix related games like Mootix Drop, an avatar (have a Mootix attached to one of your pet’s petpets, then view the Quick Ref page), & there are more than 30 items like Mootix (TCG), Mootix Pen, & Mootix Ruler. To attach a petpetpet, you need to have the pet owning the petpet you want it to attach to as your active one, then refresh your inventory.
This is an avatar item, and to get the avatar have a Mootix attached and visit the Quick Ref page.