This is awarded for getting the Tommy Gun which, on your first run, will likely turn to ink with Angel saying that it isn't that easily awarded (or something like that).

There are a few requirements needed to get this: Firstly, in the Toy Factory, there is an ink blob floating in a bowl. This needs to be activated and it will then cycle through three toys (Boris, Angel and Bendy) and an Ink Machine. It needs to be on the Ink Machine. Secondly, you need to choose the Path of the Demon. Finally, and most frustratingly, you cannot die.

A tip to help with the last one is to force close (ALT + F4) the game if you die. Save frequently at the Job Cards and you should be able to restart without losing too much progress.

Bendy spawns far more frequently (unconfirmed, but partly tested on my part) when you choose the Demon path.

If you do restart there are two vital bits of information needed: The ink blob will reset - you will need to revisit Level K and head back to the Toy Factory to change it back to the Ink Machine. Doors etc will close, meaning Bendy will get stuck and not be able to follow his usual pathing: to override this, return to a different area where he will respawn and then run back to where he had got stuck earlier, and hope.