For almost 10,000 or more years , There has been a war between humans and demons

Demons , Mainly succubus and incubus , are very good at manipulating humans and use marks to show it

You , a human , is part of a organization of humans against the abuse of humans and are trying to free them

One day , You randomly wake up in a dungeon with chains and fancy things everywhere...But you noticed a mark on you...

But more specifically , the slave marking...Which means your now owned by a succubus !?

Before you could react , someone walks in

"Thank you devil your awake...Now I can train you...Or maybe explain why your here~?"