@OPOI Plus it's not trapping her so much as she has to stay still at this point to maintain her concentration. The main thing with the shield right now is that it's draining her physically since she can't control her prana very well just yet, which will eventually make her even more vulnerable. Still, I probably didn't explain enough on how the shield works, so it's ok.
Plus the whole post taking forever thing because there's so much to reply to, that also makes it hard. ^_^" I feel your pain. All too well. Heck, I'm still trying to get my post
written, with little luck thus far.
@Xam, yeah, like OPOI said, wanting to improve and being receptive to criticism is a very good attitude to have. The only things I'll add to what OPOI said is to make sure and always keep Sephiroth's status as a villain/antagonist in mind when writing him, and like OPOI suggested, make sure to keep his power levels in mind.
I think the reason you tend to take the curbstomp followed by the other person curb stomping approach is because you've seen it a good number of times in Shonen stuff before. It works with your average shonen protagonist, since more often than not they tend to be underdogs of some kind or facing some form of powerful enemy, but with Sephiroth, it's going to take quite a bit to even make him break a sweat. Even if Gatou is really powerful, Sephiroth should be able to take him on pretty easily regardless. So just keep that in mind when writing him in the future.