>>9420078Berserk is a manga about a swordsman called Guts in a nightmarishly horrific medieval world which is being manipulated by a quartet of demons known as "The Godhand".
After about 30 chapters setting up the world and Guts quest to kill the Godhand, there is a 10 volume flashback arc explaining the lore of the series. Guts was a random sellsword who was recruited by an androgynous knight named Griffin and his second in command, a female swordsman named Casca. The three lead the Brotherhood of the Hawk, a private mercenary army who, unknown to everyone else, was created by Griffin so that he can one day seize control over a kingdom that Griffin can rule.
Over time, Casca falls in love with Guts (weakening Griffin's ability to control her, as he had gained her undying loyalty by saving her from being raped when they first met) and Guts becomes more and more disillusioned when Griffin forces Guts to help him murder a young noble's son to garner more political capital for Griffin's schemes of conquest. Ultimately, Guts and Casca quit Griffin and Guts beats Griffin in one-on-one combat when he tries to force them to stay.
Griffin, upset that his strongest warrior and second in command have left him, fucks up in his social climbing and pisses off a king by fucking his virgin daughter, resulting in him being imprisoned and tortured. The Band of the Hawk guilt Guts/Casca to rescue him, but through a serious of events, the Godhand appear and offer a broken and mutilated Griffin the power of a demon and the resources of the Godhead to achieve his goal of conquest... so long as he kills off all of his former friends and allies. Griffin does so and all of the members of the Band of the Hawks are killed by Godhead demons, save for Guts (who loses an arm) and Casca, who rapes Casca in from of Guts and basically drives Casca insane from the experience.
The rest of the series is Guts trying to find any and all way to cure Casca's madness and kill Griffin.