Mapping and shading are definitely your downfall Akashi.
The guy looks like he is wearing rosey makeup...
This tutorial is good for shading.
For the mapping, his eyes are junked up and need to be up more.
His mouth is wider than the Grand Canyon.
Try fixing proportion of the facial features, they are either too big or too small.
Also, fix that tattoo, please.
Hope I helped out a little bit <3