1-5. Toki to Meki 6-7. Bungeibu Ninen Ichinose-senpai 8-9. Hentai Comic Editor

Leader (and her assistants) of an all-girls gang gets raped by delinquents to the point of developing stockholm syndrome towards the rapists. -desudesu

Vol.01 Kuppuku Vol.02 Shuuchi no Gakkou / School Shyness Vol.03 Indication of the Darkness Vol.16 Happy Merry Xmas Vol.18 Koigokoro, Shoushin Vol.19 Zetsubou no Kyouen Joukan

For those who like their hentai kind of twisted and slightly extreme, welcome to the world of Monzetsu. In these stories it's always a little too big and a little too deep; where girls are reduced to eye-pop...