Katy Perry is a stand user!!
Yes... I know it kinda late for this drawing but well...left shark
Based on this!
http://es.tinypic.com/view.php?pic=3166avm&s=8#.VQ0RlNyHOZP
Here are some variations

Lineart/Inks.
http://gerardson.deviantart.com/art/Katy-Perry-Lineart-521535829?ga_submit_new=10%253A1426918091
No BG and separated.
http://gerardson.deviantart.com/art/Katy-Perry-No-BG-separated-521536326?ga_submit_new=10%253A1426918341