I like charlie. She's probably the only interesting female cast from the entire season ( at least until rowena came on season 10 ). And also the story is pretty forced , there's a lot of plot holes like , why did charlie leave to the motel in the first place , how come dean can't notice that sam is hiding something which is pretty freakin clear , and about the styne family at the very end of the season. that was really low , and the way the writer "killed" charlie off screen. Really ? Charlie was pretty fudging interesting and important character , she deserve a proper dramatic , intense and heroic death scene.
and for some people that said castiel could hear charlie and zap or "fly" immediately to charlie , he can't. because of the all the angels ( except lucifer ) lost their wings due to the spell that metatron did ( season 8 finale ) , so the all the angels lost the ability to zap. Although ,Metatron took his grace but but castiel didn't got cast out from heaven. So i guess he should still have wings :-/ , i'm not sure tho. I kinda hope charlie back to the series somehow.
and for some people that said castiel could hear charlie and zap or "fly" immediately to charlie , he can't. because of the all the angels ( except lucifer ) lost their wings due to the spell that metatron did ( season 8 finale ) , so the all the angels lost the ability to zap. Although ,Metatron took his grace but but castiel didn't got cast out from heaven. So i guess he should still have wings :-/ , i'm not sure tho. I kinda hope charlie back to the series somehow.