They are not continuation. I've read both of them cause of the anime and saw that it was created using both of mangas, probably because the cases in both of them are different and you can't see or feel that they are one other continuation.. However, it's your choice ;D
I personally read the other first after watching the anime. It's shorter and feels speed up an left kind of hanging. This one is is a bit more detailed with stories not in the anime. I like both just fine and they are not cont of each other or the anime. They all start about the same.
Okey... thanks @Gaisrena ... i think i would read the other first,hehe...
Yep,,, i would read the other first too because that's shorter than this one.hehe...thanks @Lon333
Which should i read first,this manga or the other one? Cz i want to try read these mangas,but i hesitate.im afraid if these two manga are continuation one to another...