Hmm,let's see... I'll try to give you some critique here from both
artistic and anatomic perspective. I hope this will be helpful as I'll try to cover up everything explaining in sections.
I'll start with anatomic since it's the base of the entire composition:
The head shape is right,chin looks good as well, cheekbones are at a correct hight.
There is one thing incorrect about the
nose.
In your drawing,the upper part of the nose is too broad and seems like it's rectangular. At some point,the nose line becomes curved,and that can be seen as specially from the angle Kurama's face is now.
That broadness there gives the impression of a feline nose.
If you noticed,the head of a feline is rather flat in most cases,and the nose bridge is continuous to the scull.
In humans,there is the nose cartilage that makes the difference,the so called 'nasal pyramid',named that way because it starts narrow at the juncture where the nasal openings are placed on the skull,then becomes wider at the lower end,where the nostrils are found.
Here it looks more like a "nasal rectangle" rather then a pyramid.
You should keep this in mind in future works.
Of course,this is a general physiological and aesthetic rule,but some people may have either wider or narrower,longer or shorter nose bridges,or even the "nasal hump",which makes the nose have a square,feel if seen from the profile. Anyway,you should consider narrowing the upper nose part and giving it a curve in the future.
Pay attention to the distance between the eyes! That distance should measure exactly one eye length worth. You can try it for yourself by measuring the distance from one temple to the other.. You'll notice it's exactly 5 times the size of an eye. So keep in mind,that at that level your head should be 5 eyes wide. 2 times for the actual eyes and 3 spaces representing distance
left temple- left eye outer corner / left eye inner corner-right eye inner corner/ right eye outer corner-right temple.
Lips. I would add more definition to the upper lip. The upper lip should look more like two stretched half circles meeting at an exact middle point,giving it a shape similar to a left-down-turned number "3". You've given him there some definition..but not enough. He's anthropological asian,while the thick,less defined lips are specific for the African people. There are rare cases of thick undefined lips seen also in other types of races though,but pretty rare and not very aesthetic.
That should be about it regarding the head.
The hair looks a little plastic.I think you wanted to suggest a light source,but he seems to have white hairs on the upper layer. You should change the intensity of white when adding it to the hair,so that it would suggest light,rather then pigmentation. For example,chose a point in perspective that would represent the place there the maximum light can be found and follow that trajectory trough the entire picture. You'll know that way there the lightest colors should be applied,and where not,add some gradients to make the transition from dark to light less abrupt.
Adding many tones of the same color is indicated for getting that effect. I can tell you know that,but I think you should apply that to every other segment of the body,not just the skin.
Moving on:
Neck- you defined the neck muscles (sterno cleido mastoid muscles) but you only did it half way.
You see,it seems as if those muscles (at least on the left side) are vanishing in the thickness of the neck. And that is wrong. The sterno cleido mastoids are the most superficial neck muscles,so they are more visible from that angle(and mostly any angle). What made them look wrong here? Well,you added shadow to the base,you even added a little light,but you didn't continue it.
You left it halfway done,as if his muscles stops there.
The trajectory of this muscle is actually explained in it's name.
Sterno (for it's sternal origin) , cleido (for the clavicular origin) and mastoid (for it's insertion on the mastoid bone- that is right behind the ear ).
So,the muscle starts at the clavicle and goes up to behind the ear,and you should follow that trajectory all the way by adding the lights as shadows accordingly.
He doesn't seem to have an Adam's apple. You should add a little bit of shadow and light there to create that,bump impression the Adam's apple gives. You should do that at about the middle of the distance between the clavicle and the skull.
Shoulders. You've made the right one shorter then the left one. Also,keep in mind that
the broadness of the shoulders is twice the size of the head's hight. So,when drawing the shoulder,consider each one of them to be as broad as the head's hight.
The clavicle is placed well but the
great pectoral seems detached from the clavicle,and that is wrong.
The great pectoral has it's origin along the lower part of the clavicle,first 5 ribs,sternum,and abdomen and inserts itself on the humerus (upper arm,around the shoulder) so,you should draw the pectoral as a continuation of the clavicle,no limiting is needed.
Here it looks as if his pectoral originates..I don't know,form the 1st or 2nd rib.
So that shadow underneath the clavicle shouldn't be there,or at least not that visible.
Other then that,the pectorals look a little swollen rather then toned...It's because of that light there that gives it a plastic feel. You should again,make the transition from dark to light/ light to lighter a little softer. Adding another 2-3 light tones before the actual vivid light there will make it look a little more natural.
The abs seem ok. You might have made them a little more defined,but that is your choice,and also,the transverse abdominal muscles (I see a hint of them around the sides of his torso,but once again,very little defined) ,you should let then be a little more visible for a more masculine,trained look.
And now the hands...ok,here I admit that I'm completely oblivious as well..but let's try and see what's wrong here.
Ok,the palm,as you may see for yourself has 5 sides if you would draw the geometrical figure. Some people draw a rectangle,but that is wrong. As you see,the thumb emerges from the base of the palm with his separate bones. That is because the thumb is composed only out of 3 bones sections,rather then the 4 ones that can be seen at the other fingers.
The base of the palm is made of attachments of little,square or round bones called the carpial bones. Those compose the attachment of the wrist as well. After that come the meta-carples,the continuous layer of bones that make the 'palm' in fact. And the last part are the falanges (the fingers and fingertips)/3 falanges for each finger/only 2 for the thumb.
So keep in mind the bony structure of the hand when drawing,as specially the fingers. Don't make them completely cylindrical. You should draw them in such manner that the joints are visible,by making the base of each bone broader.
Anyway,this would be all regarding anatomy.
Now let's skip to the artistic part.
Here,I don't have much to point out. The colors are pretty well picked,and indicate the weather and dark atmosphere. Just pay attention to darkness and light,like I said earlier.
The fabric looks wonderful. I really like how you did the folds and how you added shadows and light. Bravo.
It has that certain sculpture feel,but a bit softer,making it look real. So that's very well done.(but there is a slight mistake that I'll point out later on)
Now, about the rain.
It looks well. Yes,you did well there,but you could have added something more to actually make this have depth and gain the 3D feeling.
You made all the rain drops drawn with the same intensity and blurriness. It seems as all drops are at distance. Here's what I would have done: the rain that is seen farthest,is the most blurry and less intense colored,with smaller drops, the rain that is closest to the eye should be more visible,the drops should have a more intense color (white here) and be relatively larger.
If I wouldn't have noticed that you made some drops in front of Kurama as well,I could have thought that there was rain only in the background and that he was staying at shelter.
It doesn't really give me the feeling that he is in the middle of the rain.
Also,by the amount of drops,it indicates some heavy rain,yet I only see one drop technically fall on Kurama here,and that is the drop that hits his knee,causing that rebound effect.
You should add more drops rebounding like that against his body,or someone might think that his knee is the only place where rain falls on him.
The drops on his skin look ok,but the ones on the fabric are not necessary to be there. Fabric can absorb water,and therefor there is no need for them to stay on the surface,unless his clothing is made of some rubber,plastic material that's hydrophobic.
The explanation of water on his skin is exactly the same.
Skin=Hydrophobic Cloth=hydrophilic.
The cloth should look soaked and heavy,it's color turning darker and more attached to the skin. That would give out a very realistic effect.
Background looks fine.
Well,this should be it. I tried looking at every aspect of the composition.
All together it's a really good one and your intentions are visible and understandable,and that is important.
Now, if you'll apply the things that I pointed out,in a future drawing,there will be a visible high improvement and you'll be quite satisfied yourself I assume.
I see you're really keen on knowing how to draw proper anatomy and that is admirable.
Therefor,I'll suggest to you to get a more in depth view on the human body.
Try studying the muscles from an anatomy atlas rather then just from an art one.
Understanding how the muscles and bones are set in the human body is essential and you'll master realism in a heartbeat if you have those notions.
I'll recommend to you my sources of anatomy study (medical) but those would be an amazing help to artists as well. You may check out whatever muscle you need to understand and apply that in your drawings.
Sources: NETTER ATLAS OF HUMAN ANATOMY:
http://thepiratebay.se/torrent/5923795/Netter_Interactive_Atlas_of_Human_Anatomy_CD_iso
This is an amazing anatomy atlas,essential for medical students but a gold mine for artists as well. All the muscles are drawn by a world renown Doctor-artist and is considered the best anatomy atlas on the market.
ACLAND VIDEO ATLAS OF HUMAN ANATOMY:
http://thepiratebay.se/torrent/5079707/Acland__s_DVD_of_Human_Anatomy
This is also an amazing source of information on the human body. It's a video atlas that shows each and every element of the human body from all layers to all angles. This one is particullary interesting as it is shown on real humans
(corpses)... so you might want to check it out if you're ok with seeing corpses...if not,ignore this atlas and just go for netter. (I would recommend using Acland as well,since you can see everything as a whole,rather then on sections like in the netter one)
Well,I really hope this is helpful and that you can see what should be changed in future drawings ^_^
Amena
You might also want to check your mail...I would have liked a little help with the battle sistem 
