Nice work on the atmospheric perspective. The background is actually quite functional for this piece. The light source seems a bit confused in places on the figures, seeming to come from slightly different angles and at different intensities in places. Were you working from a preset palette? I'm a little torn on the colors used for the legs and the larger jacket. I think they would benefit from higher contrast to help them stand out from the background, but at the same time the lack of contrast does bring the focus squarely to the fluorescent green hair.
The pose for (Senry? the green-haired girl) doesn't seem to really pop. It looks like she doesn't care that she's being lifted by her arm (a very uncomfortable thing to have done to you), but her expression shows a great deal of surprise. Instinctively I think that she should be trying to use her other arm to grab Bro's fist; both to more comfortably support her weight and to try and free herself.
I was focusing more on painting techniques in this piece hence the lightning suffered a bit. Senrys position is indeed very unrealistic, but when I first sketched it it looked so cartoony and funny that I decided to keep it this way instead of having her hang like a wet noodle.