>>105867755A visual novel is a type of video game, in a loose sense. It's played by reading through the game and (in most games) making choices about how to progress the story. There's normally static art on screen of the characters/background/etc. and a soundtrack. There are tons of games like this released in Japan, more popular ones tend to get translated, and there are some developed in the west. Some also get adapted into anime. Examples of anime adaptations of VNs: Clannad, Steins;gate, Higurashi, Fate/stay night.
In a generic VN the target reader is a male, you tend to play as a male protagonist, and the story has a romance focus and your choices determine which female character you can date. This isn't absolute as there are also sci-fi, mystery, horror, etc VNs, but it's pretty common. Some of them are only a few hours long but there also massive 100+ hour VNs. Many (not all) of them contain porn from when you get to have sex with whatever character you're romancing. There are subgenres that are targeted at female otaku, where you either play as a female character (dating men), or a gay male character, there also lesbian VNs -- all of this shit is not the norm, but there are a decent number of games like this.
Probably sounds like an AI wrote that but I swear I typed it all out.