Doujinshi from different series:

Warning: Very hardcore and inhumane stories.

Volume 1: Ragnarok Online
Volume 2: Ragnarok Online
Volume 3: Ragnarok Online
Volume 4: Tengen Toppa Gurren Lagann
Volume 5: The Tower of Druaga
Volume 6: Code Geass
Volume 7: Fantasy Earth ZERO
Volume 8: To LOVE-Ru
Volume 9: Working!!
Volume 10: Asobi ni Ikuyo!
Volume 11: Infinite Stratos
Volume 12: TERA (The Exiled Realm of Arborea)
Volume 13: Saki - Achiga Hen - Episode of Side-A
Volume 14: Sword Art Online
Volume 15: The IDOLM@STER
Volume 16: Kantai Collection
Volume 17: Kantai Collection
Volume R:
Volume 19: Dungeon ni Deai o Motomeru no wa Machigatteiru Darou ka
Volume 20: Granblue Fantasy
Volume 21: Granblue Fantasy
Volume 22: Kantai Collection
Volume Vol.1 Epilogue:
Volume R2:
Volume 25: Granblue Fantasy
Volume 26: Fate/Grand Order

[guro warning]