I suggest you visit book off (https://www.bookoff.co.jp/).
The Japanese people, generally, handle their things gently and they keep their things well. So if you don't mind preloved (i.e., second hand), book off is a preloved book/CD/DVD heaven. :)
If the condition of the book is not bothered. Secondhand bookstores are cheap, there are many kinds.
There are a lot of mangas in the used book store.If you permit the condition, I can recommend it!