Tokai's residence is a location in Red Steel. It's where the game's final battle takes place.
Together, Scott Monroe and Otori head to Tokai's residence. Otori wants to kill Tokai for poisoning Mariko and Scott needs to rescue Miyu Sato. During the battle, Otori is also poisoned.
Eventually Scott defeats Tokai and rescues Miyu. Tokai tells him of an antidote that can cure Scott's poisoned friends. Suddenly, Otori shows up to kill Tokai. That's when Scott has to make a choice: Kill Tokai and never find the antidote, or let him live allowing them to get the antidote.
) The player can allow Otori to kill Tokai, which will result in both Otori and Mariko dying from the poison.
) The player can fight Otori and defend Tokai, but if the fight is lost, Otori will kill Tokai also resulting in the deaths of Otori and Mariko.
) The player fights Otori and wins, allowing all three characters to live, with Tokai as a prisoner.