Yuusha no Dorei Inmon ga Maou no Musume o Youshanaku Osou!

Buy official english version on The daughter of the demon lord arrives at the throne room and witnesses the sight of her perished father. She attempts to avenge him by challenging the hero that was likely responsible.. but gets defeated. When she next regains consciousness, she finds herself tied to a bed and unable to move. The hero then tells her that he cannot maintain his powers without absorbing mana from others.. Unable to resist due to a lewd crest of servitude, her body is ravaged by the hero.