So I'm making a Manga and my friend asked me to put her in it. This is what I came up with and she liked it. Please give Me Cnc as I need the pointers. This is the final design for colors and clothes and features, but not for proportions Spoiler
For your skills at the moment, this is good, but if you want to get better, the breasts should be smaller and the waist/hip should be a bit wider, also on the hand the index finger should be shorter then the middle finger and the little finger should be a bit shorter too, as for the other hand holding the sword, the fingers should cover the handle, also where you've shown the inner elbow is, it's too low. Hope this helps and good luck with your manga project. Also try looking at photos of real people, best way to get a better understanding of how each body part is to other parts.
The design is very int interesting and I like the expression on her face, it's like... determination and kick-buttness c:< I agree with what Anniexo is saying.The anatomy needs some work. I think the biggest things are the proportions of the head. The head and neck (almost until the shoulders really, but that could be the armour?) are very big compared to the body. And think about bones, the body is filled with joints so it should also be apparent in drawings. The arms look very stiff but I do see the difference between the upper arm and the lower arm but a little line there in the edge kind of looks awkward. Another thing is her chest area. I mean, she could have large breasts but what makes this look a little off is that under her clothes - the width of the breasts are bigger than the chest or torso of the girl herself. Remember that it's connected still. This could also be confused with how small her hips are. They should be wider. With this character's body - think about an hour glass. Cause she seems like she would have a pretty nice body. I like how you drew her legs though. The hair also looks rather stiff, hair is pretty flowy one way or the other so try thinning the ends out and remember gravity. Everything gets pulled down by that force. But this is very good. I like the style you're using. Keep practicing the proportions and anatomy! Great job! And Good luck on future pieces! c: <3