It's sooooo stiff. Sorry. If u wanna get better at drawing look up Gesture drawing. U should learn more anatomy as well. anyway about the picture. His left arm is too short and arms arnt shaped like that. he dosnt have nostrils and the under part of his nose should be darker anyway because thats where the light hits it the least. This is the biggest thing. Those eyes are way not even. A lot of manga artists forget that even in this style those things are attached to their heads. Look up the loomis method of drawing and practice it for a day and i guarantee you'll be able to draw a manga head from any angle you can dream of.