Creases?

[Bennyboi]

I know this is the most random question ever, but when looking at artwork by Jo Chen it seems to have 'creases' in them. Lines going through the art and it has always made me wonder what is it? Is it the program that she uses to paint her covers? Also, does anybody know how to digitally paint like that?

Thanks

[endofautumn]

best way to find out is to ask her yourself =)

www.myspace.com/jochencomics