忍法杀戮合战，再起。                                   于庆长之世爆发的三代将军继承人之争，                                   演变成为甲贺、伊贺的忍法杀戮合战，达到凄惨之极致。                                   在凋零的花瓣当中，为爱而生的男子与女子，                                   也梦幻而美丽地消逝——然而。                                   根据经由服部半藏的继子·响八郎所流传的传闻，                                   不知是瞬间还是永恒——                                   由两片花瓣所诞生，残存的两个遗物。                                   甲贺八郎、伊贺响。                                   各自有着与父母相似的眼眸而诞生的宿命之子。                                   时为宽永，太平之世。                                   忍者已是无用之物，其末路只有隐入黑暗一途。                                   为了凭借“血”与“力”使其基础坚如磐石，                                   甲贺与伊贺的人们，对八郎和响寄予了某个期望。                                   “契约”                                   ——身为亲兄妹，二人背负了结下契约的宿命。                                   被宿命所翻弄，在迷茫中生存的八郎，                                   以及遵从自己深切的真情，为爱而生的响。                                   二人编织的生存之路前方，诞生了未知的现象“樱花”，                                   在那里，乱世之影渐渐逼近…ccc