So I'm going to talk too much about how I did it. It's more some experiment but, I'm using a lambertian toon shader with an outline. Since the game was supposed to be realistic I still have some trouble figuring out what art direction, I4m going to take.
I just finish the shader and I'm pretty happy with it. The material editor is a real force for game development. I know a bit of hlsl but I wouldn't be able to recreate such a complex shader with it. So the cloth are made with a different shader that the skin. I use and environment map to create an highlight and some specular map and ambient occlusion map. It give me a really nice look on the cloth. I try to create a spec map accordingly to the fabric.
So this character so is going to be change. I'm starting a new design for him. Someing less realistic or at least a bit more manga. I'm not looking for something cartoony just someting like realistic manga from mamoru ooshi. or satoshi kon. I still don't know where this game is going so I may do a lot of tryout to found out what art direction is more fitted for my ambition.