wolf cut
A wolf cut is a type of haircut that has more hair volume on top, and thinned-out hair starting at the base of the neck.
A variant of this style has been called the "jellyfish cut" due to its shape - with a rounded "body" (the short layers) and billowy "tentacles" (the longer layers):
Do not conflate this tag with the mullet hairstyle, which is cropped at the sides of the head (Danbooru post #5940624).