It depends. In some niche circles that are interested in the intersection of technology and love stories, 'love machine novels' might be quite popular. However, in the general market, they may not be as well - known as more traditional love stories or mainstream science - fiction novels.
I'm not sure if there are widely known 'popular' spanking machine fanfics in the mainstream sense. Fanfic communities can be quite niche, and such a specific concept might not have broken into the general popularity. However, within certain specific fandoms that have a taste for more unusual or kinky concepts, there could be some well - known ones among that particular group of fans.
Well, 'The Time Machine' is a must - mention. It takes the reader on a journey to the far future, showing different species that have evolved. Then there's 'Time and Again' by Jack Finney. It has a really interesting premise where the main character travels back in time to 19th - century New York. And 'Doomsday Book' by Connie Willis, which sends a character back in time to the Middle Ages, dealing with the challenges and differences of that era.
There's 'Doomsday Book' by Connie Willis. It involves time travel to the Middle Ages. The story weaves together different time periods in a complex and engaging way. It shows how actions in one time can have far - reaching consequences in another. It's a great example of how time machine novels can be used to explore different eras and the human condition within them.
Sometimes, there are original characters created specifically for the fanfiction. These could be companions of the time traveler, like a local from a particular time period who joins him on his travels. They add new perspectives and relationships to the story.
Some popular ones might include 'Sword Art Online'. It has a unique concept where the characters are trapped in a virtual game world, which can be related to the idea of a vending - machine - like discovery in the sense that the characters are exploring a new 'world' full of surprises. Another could be 'Re:Zero - Starting Life in Another World'. The main character's journey of constantly restarting and learning in a new world is quite engaging, similar to the idea of finding different things from a vending machine each time.
I'm not aware of any extremely popular'machine child visual novel' at the moment. However, in the niche of visual novels, there could be some indie works that explore this concept.
There doesn't seem to be any widely known and popular 'baby making machine fanfic' stories. The concept is quite unorthodox and not in line with the typical themes that tend to gain popularity in fanfiction. Most popular fanfics revolve around the relationships and adventures of established characters from well - known franchises. A 'baby making machine' concept is more of a very specific and idiosyncratic idea that might only appeal to a very small subset of fanfic writers and readers, so it's not likely to be a common or popular type of fanfic.