The light novels! Those are your next go-to! Here's the Amazon page. There's currently three volumes in print but more available digitally and presumably the webnovel as well https://www.amazon.com/dp/B084G8RCRC?searchxofy=true&ref_=dbs_s_aps_series_rwt

Amazon doesn't have them all listed yet btw, at least 7 volumes have been confirmed for release and should appear shortly