anyone have any ideas for my book?.....

ok i need some help im stuck..... and need some good ideas for my book.........heres what its adout.........

ok so there's 3 kids(all girls) there names are....... kara she's 14teen,cody she's also 14teen, and sallie she's 13teen.....so one 日 thay find this notebook and open it up, its adressed to them... it 発言しました bewarnd for darkness is comeing in the shape of a boy....one of あなた will turn...one will run and hide... the one left can save it all... if they dare to try....

thats all i got have anygood ideas.....
please help.....