This is great! ! I wonder if Kat herself has looked at this!

I would write a critique but I need premium access. =[ Here I go!

First, the good bits: overall anatomy in terms of proportions and relative sizes is very good! The line of action of the piece works very well and the pose does seem to 'flow' pretty well. I’m pleased that you’re trying to push your boundaries and move outside your comfort zone of drawing characters standing up, arms by their sides and face-on – this pose is pretty challenging! Given the character, the cheeky grin is also very appropriate. XD

I also like the photo/drawing combo! Her bent right leg does actually look like it's creased the bedsheet - did you plan the drawing when taking the photo? Colour scheme is also very well selected, with a creamy look to her skin and some outrageous blue hair, so good job on that too!

The not-so-good stuff: it's great that you've given shading a go, but you still don't quite seem to have a grasp on your light sources. The glare that runs on the top of her hair indicates it's raised to the right of her, but the inside of her ears seem to be providing their own light! Her right ear and the right side of her face wouldn't get much light from where it's positioned, seeing as it's both hooded and facing away from the source. Little details like the shadow on her nose being on the other side, the somewhat blotchy shading effect on the left side of her hair and the creases on the right side of her jacket... dress... thing having a glare when her body would be blocking the light should also be considered.

While the anatomy has a great 'feel' and is convincing at a glance, there are a couple of details that could use some work. She has a super-elongated forearm with an elbow that's a tad too thin, for example, and her right shoulder seems to be bursting out of her collar. The anatomy on her right leg is muchos good, only perhaps a little too thin around the knee cap, but the calf on her left leg is a little off. The bulk of the muscle, and hence thickest part of the leg, should be nearer the knee rather than in the middle and it probably shouldn’t get quite so thin around the joint.

It feels weird commenting on the ears but... given that they seem to 'sprout' from quite far back on her head, shouldn't we only be able to see the tip of the right one from this angle? It's great that you've actually considered creases, but you seem to have drawn them as only sticking to the sides of her clothes, when creases tend to run much further into the middle and cause shadows. Given her pose as well, wouldn’t there only be creases on her front rather than her back, where her dress isn’t crumpled?

I hope this has given you some food for thought! Sorry it’s a tad long: I really do like the picture, there’re just a couple of niggling details that could use some improvement. Keep up the good work!

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Keep Calm and Carry On