Hayate wants Nagi to attend school on a daily basis. One day, however, when returning from school, Nagi forgets a notebook, and as her butler, Hayate goes to the academy to get the notebook. However he arrives at night.... in an area that's supposed to be haunted!
But fundamentally, except 
under extreme circumstances,
Pero, básicamente, excepto 
nuestras circunstancias,
Só que na verdade, exceto 
em condições extremas,