These dating sim elements are often referred to as Romance Sidequests in the RPG genre.I am working on a Dragonball Z dating game, This will be a mix of a visual novel and a dating simulator game, where you can date the handsome Guys from Dragonball Z, such as Vegeta, Goku, piccolo and more....
In fact, many romance games are Visual Novels, which is a much different game style.
(See for example, the difference between the series, which is very close to a Visual Novel style of gameplay, and the DOA Xtreme series, which is the closest thing to a true Dating Sim with mass-market appeal in the US.) If the game plays out like a Choose Your Own Adventure, that's a Visual Novel.
In Fate/stay night, for example, the way the player character behaved towards non-player characters during the course of the game affects the way they react to the player character in later scenes, such as whether or not they choose to help in life-or-death situations.
This would be far more difficult to track with physical books.
Some Sim Date games have been made into Harem anime, though the result is usually nothing special due to the removal of sex and the fact that the narrative can no longer focus on any single character.
Because there is almost no market for true Dating Sim games outside of Japan, it's a frequent misunderstanding among western gamers that "Dating Sim" is the general term for all ren'ai (romantic love) games.
If it feels like you're playing an RPG, trying to keep track of everyone's feelings about you and giving out presents, that's a Dating Sim.
In recent years, there have been many Role Playing Games that incorporate dating sim elements.
Decision points within a visual novel often present players with the option of altering the course of events during the game, leading to many different possible outcomes.
An acclaimed example is Zero Escape: Virtue's Last Reward, where nearly every action and dialogue choice can lead to entirely new branching paths and endings.
Many visual novels use voice actors to provide voices for the characters in the game.