Hayate's elder twin sister, Kurogane Nagi, returns to Tenchi Academy, and asserts that she, not Hayate, should be the one to partner with Ayana. When Hayate lodges no objection to this, she is met with an explosion of anger from Ayana!
Hayate flees to the hills and falls in with Yanagi Makoto, a sword-bearing student about to graduate from Tenchi. Meanwhile, student council president Amachi Hitsugi is arranging a "farewell party" for this graduate: a massive all-against-one "battle royal" involving every swordbearer in the school!
And now, with preparations complete, let the curtain rise!!