I came up with a new idea for comic/manga,what do あなた think of it?

Its about this boy named Kaoru who,in the middle of the night is being chased によって some kind of monster but apperently a mysterious girl who is a slayer kills the beast and saves him then flees. The 次 morning,Kaoru comes to school and finds out that his シート, 座席 has been moved to sit beside their new, uncivilized classmate named ______(need help with names)___ who does nothing in class but sleep all 日 and when awake ends up missing,acting weird または at the guidance coordinator.Apparently,he has been waiting since last week for her to thank him for saving her when she almost got hit によって a ball and he gets hit instead and is embarressed instead of her,the 次 日 he saves her again but this time によって getting hit によって a car though she still have not yet thanked him.Later that evening,he is ends up being chased によって another beast and the slayer-girl saves him again and she says "thank you".It turns out that slayer-girl is really sleepy-girl but in a much taller,faster,agile,stronger and もっと見る powerful form that she takes during certain times and now promises to protect Kaoru in return and realizes that the reason Kaoru has been a target was because he was the one chosen with a great responsibility and mysterious powers that he has yet to overcome.Oh yeah,sleepy girl is quarter beast