Talk:Re:Zero kara Hajimeru Isekai Seikatsu/@comment-188.176.12.190-20160918202153

does anybody know how much the anime adaption covers the manga? since there's only 9 volume (inofrmation from wiki

and what's the difference between arcs and volumenes. why i asked is beacause, that some says that the web manga have up to 6 arcs, and my questions is: does arcs not usually contains several volumes?