People need to read better it's not really hard, its just a lot explain visualy instead of with expository dialogue...
Santa clause also know as tolka "master" she's german and she is the Doll devil, She work for germany... for the job she always ask 4 young child, 3 of them she use for sacrifice for the contract with devils.. (as we see we see in the finger scene with the 4 child chapter 63 pag 14) and 1 she keep it and raise it with care to make them devil hunter and in the end perfect dolls (chapter 63 pag 4, also as human they can make contract with other devil and use their power), grandpa was one child she raise (probabily a long ago) and a perfect doll from the start, and tolka was the next one (and the child not cover by the finger in chapter 63 is gonna be the next one after Tolka). her mission is to kill makima, to accomplished that she needed more power so she made a contract with the devil of darkness, the chainsaw in exchange for a fragment of his flesh (and as we know from the gun devil, fragments of a very powerful devil can power up another devil)
-shapeshifter brothers 2 are dead, one was kill by power with kobeni car. the second one was kill by Yoshida in a alley. the third is still alive, quanxi throw him out the window and basicly save him from the hell trip.