ok, ill tell you whats wrong. Folds in the pants are all wrong, way to dodged, with black pants, look at your folds, there black, it just gets darker, they arent highlighted in some places, its just black, and darker black, no grey. There a fold near his crotch, these are where many fold are supposed to meet, i see no folds. The jacket is very blurry, and by the render is kind of poorly done, it has some wierd shadows and wrinkles that just dont look right. On the last 2 folds on the pants, it looks like you copied and pasted another fold on top of the pre-existing one, and it makes a square around the fold that overlaps your other fold. Thats alright, just belnd it in more. Im kind of happy that you didint give him that pink/red darksun skin everyone overuses, but it still looks wierd, you have some brown/red/and way to many highlights on the pecs. Looks like hes wearing to much skin cream that hes glowing. The muscles on the neck look unrealistic, they are too small and they dont bulde out, like a real neck. a real neck looks like this: / \ / \. Buldge your neck, youll see what i mean. Your missing a lot of neck muscles, like his neck bone. And the face just isnt trunks, he looks too grown up, trunks was still a teen when he went to the future..
There, happy now?