NuiNui (ヌイヌイ, Nui Nui) is a guide for Area D, who welcomes the new prisoners and explains them the rules.
Nuinui looks like a short man with bunny head and thin legs. He have 3 crosses: 2 on each end of his ear and 1 on his forehead. He also uses a cane with a heart shape at the top and a tie with heart again.
Nuinui looks kind and cheerful person, but he also have a cold side and don't mind killing someone to set up an example.
Nuinui came of the Gate of Area D, welcoming the new prisoners and telling them that he is the guide and will tell me about the rules. One of the prisoners got annoyed by him and asked him who he is, but Nuinui told him that using such language is forbidden and gave him infraction. That annoyed the prisoner more and he continued, while Nuinui gave him 2nd and 3rd infraction, then his men killed the prisoner. Nuinui said that he didn't even had the time to explain the rules and the three-out system. After he explained it, he welcomed the prisoners to step inside the gate.
Stepping inside the gate, there was a hall, where Nuinui told the prisoners they will go through a ceremony and each one will enter though another gate in between 3 minutes and that 300 meters inside, is their goal line. Once the prisoners started entering and it was Jin's turn, he found it strange that his name wasn't in the list, but one of the guards told him about Jin and Mika's situation. Then Nuinui asked them to go in the guard room, since he needs to speak with the administration. After contacting the administration, he told Jin and Mika, that they don't need to go through the gate and a car will come to pick them up, but Jin told him that they want to go through the gate with the rest of the prisoners, which surprised Nuinui.
The crosses in his ears and forehead on his rabbit head is able to glow and shine. He shown his ability to warn an altered, each warning brighted on different cross. This ability can be mechanical or altered ability.