The bottom of the back and the sides are left alone so the cosplayer can trim it to whatever length looks best on her head, which is why those areas are unfinished.
I've wanted to style a Roxas wig for a very long time. I really love his hairstyle, but since he wasn't my first character choice when it came to cosplaying from Kingdom Hearts, I never really had a good excuse to style a wig for him.
I got an offer from the owner of Arda-wigs to style a wig for her Ventus cosplay. Though I am closed on commissions, I chose to take her offer since: it was a good deal, something I really wanted to do, and I won't have to mail it (Arda wigs is going to have a booth at Katsucon, so I'm going to deliver it).
I bulked up a wig head with newspapers and tape so it'd be more accurate to her head size while stying it. She provided 2 Magum wigs, which I combined into one thick wig and styled with Got2b hairspray and fabric glue (for the very tips of the spikes). She says she's really picky so she may or may not end up using it depending on how it looks on her own head. Hopefully she likes it and that it all works out for her. I'm personally happy with the result :3
If you would like more info on how I styled it, I used the same techniques that I used to style Cloud
it's beautiful O^O