These are by Seiko Omori. The 3D girls look a little stoned, but they're so charming and sweet. And then the 2D ones are more like fashion illustration--so edgy and cool with their dash of anime style. I love that Omori utilizes two diametrically opposite styles, but they somehow still feel cohesive together. I think it's the rosy cheeks and faraway glances that do it.
(This is my favorite 2D one. I think I may have to print it onto transfer paper and make a purse or tee-shirt out of it.)
P.S. Sorry for so many image dumps lately! I just can't help but share it when I find illustrations I like (being a wannabe-illustrator myself and all). Plus, it helps me to remember them for my own projects and stuff :]