Maybe, now that I'm actually back to paying attention to my obligations, I might be able to get this challenge thing out every day. Like you're suppose to. (Except Saturday and Sunday. I have no internet over the weekends.) Funny, I had almost forgotten how I wanted to answer this…
Legal Drug (AKA: Drug & Drop)
I don't have a very good reason for this - only that I never really clicked with the characters. Some would say that is because there has only been three volumes released (at least in my country) and that is too little to get attached to the characters. I would rebut that with the simple fact that I felt more for the characters of Wish after only one volume.
I will keep buying it (if it ever gets released again in this country) however, I just don't care for it as much as much as I do the rest of CLAMP's work.