I ended up on an extremely crowded train with a seemingly innocent girl and performed penetration groping! Since she couldn't move or escape, I took advantage and... but that would be too pitiful, so I decided to penetrate through her panties! The intense sensation of penetration made her start to feel it, and she became so aroused that her panties were soaked! Her innocent body, flushed with shame and pleasure, was no longer satisfied with just penetrating through her panties, and she began to demand real penetration herself!
