Your photos look good, when you are outside. You often find good lighting in the shade. Even with your low-light shots, you were able to work with available light without using flash, for the Devil May Cry, romance photo, and the Tidus, water fountain photo. Your skin tones could benefit from some warm color balance.
Your compositions are generally very good. The locations are often stunning. Just watch out for cropping feet out. The Dutch Tilted shots are usually detracting, rather than enhancing the shots, but they could work well if done with more thought.
It was kind of interesting on your portrait of Aizen, you found symbolism in the dark and light, lighting effect. I know it was done with your shutter being too fast for your flash sync. Maybe it was a happy accident, or a very well planned technique. Either way. It works well for this.
I recommend for you to get a flash that can be aimed at the ceilings and walls, rather than only directly at the cosplayers. You can get some interesting portrait lighting from bouncing your flash.
Even if you were not fairly new with a DSLR cameras, I like what quality you can create.