Fast and high-contrast responses with low driving voltages in twisted nematic (TN) cells are achieved for anisotropically oriented structures of liquid-crystalline physical gels. They are prepared by hydrogen-bonded aggregation of an L-lysine-based gelator in nematic liquid crystals. When the mixtures of the nematic liquid crystals and the gelator are prepared in TN cells, fibrous aggregates of the gelator align along the twisted-nematic orientation of the liquid crystal, forming oriented phase-separated structures.