Origin: Y/N Ashborn

Y/N Haruyuki is an ordinary human who is mysteriously transported to the world of his favorite MMORPG, Cross Reverie, with the appearance of his own character in the game, Shadow Monarch, Y/N Ashborn.

Y/N found out that he was summoned by two young girls, the flat chest pantherian Rem, and the busty elf Shera. When they are about to finish the ritual, the spell rebounds, and they end up with magic collars stuck on their necks, thus becoming his slaves instead.

"What the fuck is going on!?" Y/N thought with a very confused expression at the sudden events. Firstly, he was summoned to be a slave and now he found himself owning the owners who were supposed to be his owner.
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[Disclaimer: How not to summon a demon lord is a light novel series written by Yukiya Murasaki, illustrated by Takahiro Tsurusaki. The credit goes to its rightful owner. I don't own anything and just write this for fun and entertainment.]