N2R refers to the TSAB team formed by the four reformed Numbers who were adopted into the Nakajima family: Cinque, Nove, Dieci, and Wendi. The moniker "N2R" refers to where the four of them stayed during their rehabilitation: Block "N", Room 2 of the Maritime Detention Center on Midchilda.
N2R debuted in Sound Stage X.
In an ironic twist, three of them (except Dieci) had been involved in the maiming and kidnapping of their future sister, Ginga Nakajima, during the JS Incident.