Coffin of Cerebrum

A forbidden game played in an evil castle of madness with the cursed relic "The Coffin of Cerebrum." Captured maids, princesses of fallen countries, and others are forced to play the game, and while the winners survive, the losers are used as comfort women by men driven wild by lust, becoming sex slaves... Punishment succumbs to pleasure while the Coffin of Cerebrum tests willpower and deep desires of each opponent. A dark fantasy gushing with eros so thick you can smell it.

(Source: Project-H)

1-7. Cerebrum no Hitsugi (セレブラムの柩,Coffin of Cerebrum)
8. Moonlight Flower
9. Ancient Queen (エンシェントクィーン)