0 - Really bad. Nothing good at all. Leave this manga alone.

5 - Okay and decent. Nothing special but not bad. Only to be read when you have time to waste.

10 - One of the best mangas you'll encounter

The rest you can probably just figure out. 🙂

One thing I don't understand though is why 5 is often used to rate something bad. It is in the middle of the system so shouldn't it be used as mediocre?