Where can I find the complete novel of this amazing manga?!
You can find the novels on baka tsuki:
https://www.baka-tsuki.org/project/index.php?title=Maru-MA
Also, if you'd like to see what the kkm community is up to, please check:
https://www.tumblr.com/tagged/kyou-kara-maou
Thanks so much scanlators...a whole day with a roller coasters of emotions.... I hole Shinvo would say mean he does not need the ring cause they don't need objects for their love....please just admit you need each other.. ヽ(`Д´)ノ