The Love System (恋愛進行, Ren'ai Shinkō lit. Love Progress in the Japanese version) is a gameplay feature that appears in Fire Emblem: Genealogy of the Holy War. The basic idea behind the Love System evolved into the support system featured in later games, as well as the marriage and child mechanics that appear in Fire Emblem Awakening and Fire Emblem Fates.
Playable characters can fall in love with other playable characters of the opposite gender. Which couples fall in love is determined by the player's actions. Select playable characters such as Sigurd and Deirdre are not eligible for this system, as their relationships are guided by the story.
If one of the playable female characters in the first generation falls in love and marries, her child will appear as a playable character in the second generation. If a female character does not fall in love and marry, her child will not be born, and instead a substitute character will take the child's place.
Female characters start off with a certain amount of Love points with all of the eligible male characters. Each turn (but only up to Turn 50), they will gain Love points with each male; the exact amount gained per turn depends on the male. Love growth can be sped up by ending turns with female and male units standing adjacent to each other (making the couple gain 5 extra Love growth per turn) or by initiating specific, time-limited events. Love growth is further affected by a hidden Jealousy System.
Once a female reaches 500 love points with a male, they become married. Whilst married, the couple has the option to transfer their individual gold reserves to each other, and they also receive a combination bonus if they fight adjacent to one another.