HATOKO-SAN TO LOVE COME

The story is about Hayato Heiwajima, an ordinary guy who is the main successor of his grandfather's company, Heiwajima Industries. His maid, who is also his close relative, childhood friend, and demon instructor, is responsible to teach him how to deal with females and not so easily be fooled by others. The problem is that her teaching methods go beyond the ordinary just a "little bit".