Board Thread:Off Topic/@comment-29646689-20171007145932/@comment-32836295-20171009112713

" After Bendy was defeated by SHENRON, the remaining Malice pulled itself together to form this bestial creature. [...] This form is considered to be Bendy's original, although in this state, his awareness has been consumed entirely by Malice, and all he knows is a desire to rampage and destroy."

This is proof that the "ink" is Malice.