1. Select a mission.
2. Once the game starts, hit ESC or back to bring up the menu.
3. Type the word “honorless” in the menu. There is no text bar or anything; just type it in the menu itself. A message will then pop up and say achievements can’t be unlocked when cheating.
4. Exit the menu, and then hold “insert” and the number. 1 = hyato, 2 = yuki, 3 = mugen, 4 = aiko, and 5 = takuma
5. and proceed to play out the level however you see fit.