Kouga Ninja Scrolls was written by Futaro Yamada and is the original novel that the Basilisk anime and manga were based on.

The shogun Tokugawa Ieyasu has absolute power over Japan, and he has a plan to write the next thousand years of its history. Two rival ninja clans will meet in a battle to the death, and the victor will decide who rules Japan for a millenium. But in the midst of this bloody war, an unlikely romance blooms between Gennosuke of the Kouga and Oboro of the Iga clan.

Gennosuke is the next leader of his clan, and Oboro a great warrior in hers, so their fates are inextricably bound up with their families. The star-crossed lovers are faced with a fatal choice between true love and destiny. Can their romance conquer a 400-year rivalry? Or is their love destined to end in death?