Wasn't Dr. Spaghetti the one who is responsible? I remember this one(the nightmares won't leave me... [shivers], since I don't really understand Japanese and I just glanced over this doujin, I might be wrong... Or! Did Nanoha side with the doctor? To tentacle rape Fate? Oh my God! NOOOOOOO!
I remember reading this doujin and agonizing over Fate getting tentacle raped. Then I see this page and I'm relieved that Nanoha's come to save Fate but then she joins in on the tentacle action.