Biko 2 is a Japanese 3D stalking simulation. You play as Inagaki Tetsuya, a guy who stalks pretty girls. The game starts in "adventure mode" where you are looking for objects that you will need later. When you see a girl that you like, you attempt to follow her through the city, trying not to alert her about your presence and not to lose her at the same time.
Catching up with the girl invariably leads to a rape scene, which is depicted through pre-rendered images as well as interactive 3D. Depending on the choices made by the player during the sexual intercourse, the scene will end in different ways, even including the possibility of the girl becoming romantically attached to the protagonist.
There are five girls in the game, each with unique images, city stalking levels and final scenes.