Alright, I'll try my best to critique according to your style.
I gave a 4 for the vision because you have a pretty good idea for what you are going for. I gave a 4 for originality because I like your idea and concept. I gave a a 3 for technique because there are some things you can improve on. for example, Terezi's torso is a bit thin. There are also too many too many clothing folds bunched at the center. plus her horns are a bit too far back. I gave a 3 for impact because this doesn't leave a lasting impression on me.
Now for the good things C:
Right off the bat, I noticed how you draw arms. And let me just say that you can draw amazing arms XD
Also, the hand is well drawn and does not look broken or awkward. Whew! (hands are really hard to get right) And I like how you designed Terezi's hair.
Lastly, you have an interesting vision for how Terezi draws Prospit. You took in mind that she's blind so Prospit wouldn't be super detailed and accurate. Great Job!