One game series that often includes dating, with the goal of marriage, is the farming sim series Harvest Moon.
The subplot of dating is more focused towards choosing one of several girls or guys (dependent on the player character's gender) and offering them presents or joining them on events in the game.
Dating sims such as Tokimeki Memorial often revolve almost entirely around relationship-building, usually featuring complex character interactions and branching dialogue trees, and often presenting the player's possible responses word-for-word as the player character would say them.
Dating sims such as Tokimeki Memorial, and some role-playing games with similar relationship based mechanics to the genre such as Persona, often give choices that have a different number of associated "mood points" which influence a player character's relationship and future conversations with a non-player character.
There are also GL games, which focus on female/female relationships, and BL Games, which focus on male/male pairings.
There are many variations on this theme: high-school romances are the most common, but a dating sim may also take place in a fantasy setting and involve such challenges as defending one's girl from monsters.
The Star Ocean series of RPGs also feature dating sim elements in a similar manner.
Some Japanese dating sims may allow the player to have romantic or sexual relationships with characters in their teens.
While the two genres often share a common visual presentation, dating sims are sometimes considered to be more statistically based than the "choose your own adventure" style of visual novels.
Live from San Diego, the dating capital of the world. Bachelors and bachelorettes, warm up those dice and prepare your character sheets. Select audience members get roll their own charisma check against the cast as they shoot questions to Keyleth, Percy, Grog, and the rest of the team to see who walks away with the hand/sword of their favorite character.