Japanese games with erotic content. Mostly in the form of Visual Novels.
There are different types of eroge;

Bl Game; A game focused on two males that.. uhmm.. You know. It does not necessaryli have to have erotic content in it, but most of them do. Eksamples on Bl Games, include; Hadaka Shitsuji, Kuro no Tsuki, And all of Nitro+Chirals games. (Bl stands for Boisu rabbu gamu)

Nukige; Lit. Fap game. Yeah, that pretty much gives it all. There does not have to be a story, people should just be able to fap to it.

Nakige; Games that make you cry your eyes out. These games are meant to have an emotional impact on the people playing it. This category includes games like, Clannad, Little Busters - All of the games made by Key, go under this category.

Otomege; Lit. Maiden game. It's a game where the main character is female, and is supposed to get as many guys as possible. This category includes games like; Starry sky, Uta no prince-sama etc. (Many of them get an anime after release of the game)

Galge; Games where the main character is a boy, and is supposed to get as many girls as possible.

Gl game; Girlsu rabbu gamu

An ergoe, (erochikku gēmu) is a Japanese video or computer game that features erotic content, usually in the form of anime-style artwork.

In English, eroge are often called hentai games in keeping with the English slang definition of hentai. This is sometimes shortened to H games.

In Japan, eroge are also referred to as 18+ games

software that features erotic gameplay. requires lots o tissues. Also a software required for otaku to multiply. Must have different game titles to ensure otaku lifestyle.