The Nagatoro Saga

Originally an imageset by the hentai artist 774 (also known as Nanashi). Then LWB translated it to English and while they were at it, they also made it into a visual novel. The actual visual novel part can be accessed from the New Game option in the menu and is a kinetic novel with no sexual content. The New Game+ option leads to the same story, but with added choices and bad endings (usually nonsensical, some contain sexual content). The release also comes with two short 3D hentai videos and a very short hentai minigame, all of them completely unrelated to the VN.