Kazue Kato is an excellent mangaka and illustrator (is a woman). She is the one who created the popular nowadays manga called "Ao no Exorcist" (Blue Exorcist).
Her art work is really impressive. Very colourful, great designs, very clean drawings with a lot of feeling and imagination. They are very charismatic and you have the feeling that by just seeing one of the illustrations you can make a whole new manga from it.