The service uses multiple DSLRs to take snapshots of your head, render it in 3D, and then print it out in plaster using a 3D printer. Hair, make-up, and coloring are added and then your head is stuck on a little plastic doll. You can then take said doll home and, I presume, stare at it until it starts to move.
The service costs 138,000 yen and is popular with new brides who want to capture their hairstyle and make-up in miniature before the big day. The heads are so detailed that they’re scary and I suppose there is some possibility for misuse if your doll falls into the wrong hands.