In the fourth OVA of this sci-fi post-apocalypse style anime the main girl, Mayumi, gets kidnapped by a group of mutants in some old city ruins. She spends her time, bound hand and foot and her mouth gagged with a big cloth. She spends a little time struggling in her bonds before the hero tracks her down and sneakily frees her.
Thanks to scarface over on the Western Civ Board for finding this scene!