Zero's DLC is the story of how she and Michael meet each other.Despite his sexual antics, Octa truly, genuinely loved Three and the ending shows him crossing the Despair Event Horizon from over how far she has fallen. He begs and pleads for her to stop as her sanity slips away, going into disturbing detail over her methods of toying with the lives of innocent people. You'll truly feel sorry for Octa as he is horrified by how many people Three tortured, experimented on, and ultimately killed for her research and obsession with humans as dolls. However, Two placed a trap to kill all those around her so they again both die together (with the other disciples) while Cent says that he is here for her. In Branch C, Two again goes insane without Cent beside her, but this time Cent decides to put her out of her misery.As they die, they're comforted that they will be together forever and they summon an Angel to at least make sure Zero goes down with them. When they are reunited, Cent immediately betrays Zero and returns to to Two's side.
Without Cent, Two lost her reason to the Flower.
The sight of this coarse, murder-happy Intoner trying to physically push Mikhail back from going through with it is strangely heartbreaking.