Chikan: Shoujo wa Etsurakuiki no Densha ni Notte  

恥感～少女は悦楽行きの電車に乗って～

Shiori is a reserved individual. on one occasion, while on a train, an unknown person touched her inappropriately. although she felt uncomfortable and wanted to put a stop to it, she was unable to express herself due to the situation. over time, however, she became increasingly attracted to these actions.