Elfiora

Elfiora is the het ship between Eliwood and Fiora from the Fire Emblem fandom.

Canon
Eliwood is one of three main lords in the 7th Fire Emblem game. Fiora is a pegasus rider, mercenary and commander of 5th wing of Illia pegasus knights.

Eliwood first meets Fiora when she is in a suicidal mission to avenge her dead companions, she is convinced by her younger sister give up her revenge and join their group that was commanded by Eliwood.

Eliwood worries if Fiora is adapting well in the army, and upon realizing that she tends to think too much on others and overworks herself, he wants her to not be so harsh with herself. He is known to offer a listening ear to the concerns of his troops, as evidenced through his  interactions with Fiora, where he asks if she is comfortable with the duties that she performs as a combatant.

Eliwood is also shown to be very much aware of the inescapable difference between his status and that of people like Fiora. While he expresses the idealistic notion that he sees himself and his army's members as equals, he recognizes that these words are ones spoken from a position of privilege, a position that Fiora is unable to access herself by virtue of her social standing and harsh upbringing. This recognition is translated through him making an effort to learn more about the mercenary culture of Ilia that Fiora is born into, granting him the opportunity to better empathize with her struggles. When he asks her to give a chance to be happy, she is taken by surprise by Eliwood sudden embrace and desire to protect her and make her feel better with herself.

The two eventually get married to the dismay of the Lycian nobles who protested, and they have a son who also hold the ideals of his parents of uniting everybody as equals. Their son Roy eventually becames the Hero and protagonist of the game Binding Blade.

Fanon
Binding Blade game provides the information that Roy's mother liked flowers from Illia, the birthplace of Fiora and possibly alluding to her name that means Flower in Italian.

Eliwood and Fiora has been  considerably popular among fans since the game's release. The relationship has a lot of aspects that appeal the fans: couple in love fighting together against their difference in social classes, warrior woman marrying a nobleman, war companions becoming something more,  and idealistic prince with hardworking lady. The fact that Eliwood is cares for Fiora and that Fiora is a more stable and serious presence by his side balance their personalities.

The pairing shows as an option for those who like Eliwood with a woman that is independent, powerful, doesn't depend on a man to be safe and can take care of herself. Also unlike with Lyn or Ninian, she doesn't leave anything important behind as she doesn't lament leaving her homeland like Lyn does, nor she has her lifespam shortened.

However, the pairing has received competition from fans who prefer Eliwood/Lyn, Eliwood/Ninian or Fiora/Kent. Particularly there is strong friction with Elilyn  and Elnini shippers, largely due to the game system of multiple canon endings and arguments over which is 'most canon' or 'most deserving' of being canon.

Trivia

 * If Hector marries one of Fiora's sisters, Florina or Farina, then Lilina will be Roy's cousin.