Don't think I have read any manga I truely hate, usually I like just about everything since I stick to a particular genre and read reviews and stuff before reading or buying it. Here are three im not too fond of though:
1. Uncivilized Planet - Tries to be shocking for the sake of being shocking. Not much of a story, male lead was a pussy. Was only two volumes long though.
2. The Kurosagi Corpse Delivery Service - Concept for it seemed interesting, and its published by Dark Horse which I like
. I enjoyed it to a certain extent, but I dont like how every chapter is its own story. Based on volume 1, there is no continuing story. 1) Dowser finds body. 2) Monk listens to the dead persons wish. 3) The group fulfill wish / catch murderer. 4) Repeat every chapter.
3. Blame! - I know I know shut up for a second and stop flippin out. I know this one is pretty popular but I haven't been able to get into the story. Will try it again soon, I like the art alot.