Zepar

Zepar (ゼパル) is the sixteenth highest-ranking demon of Hell and Furfur's twin. Zepar always appears in unison with Furfur when summoned, and has the power to seduce humans. Zepar can also grant unlimited defensive power and even brief immortality to those who contract them. Zepar's gender is ambiguous, though it is stated that Zepar's gender is the opposite of Furfur's.

Personality
Like Furfur, Zepar is very dramatic and over-zealous in every move made, talking with the airs of an actor on stage. Zepar also frequently uses masculine speech patterns.

Dawn of the Golden Witch
The first time Furfur and Zepar are seen is when Shannon and George challenge Kanon and Jessica for the love gold butterfly brooch which can grant love to one of the two couples. Furfur and Zepar call for Beatrice the original owner of the brooch to supervise the challenge. Noticing that there are two Beatrices, the twins make jokes about it, and then allow "chick Beatrice" to take part at the challenge to win Battler's heart.

The first part of the love trial is solved with Beatrice's victory and the two demons let happily join Battler to the challenge by Beatrice's side. After the trial is over Zepar and Furfur give the brooch to the winning couple and bless their young love.

Requiem of the Golden Witch
In Requiem, Furfur and Zepar appear as two actors on the stage of the show presented by Clair Vaux Bernardus. They mainly comment on what Clair has shown and interview all the characters of the story one-by-one. As previously hinted in Dawn, it is confirmed by Will that Furfur and Zepar were added to the previous game and to Requiem to enlarge the mystery about Beatrice's gender, so in a way the two demons are also connected to Beatrice.

Ougon Musou Kyoku
Both Furfur and Zepar also appear in Ougon Musou Kyoku, where they introduce every match, and they guide the player through the main menu. They can be seen also in the opening video.

Trivia

 * It is heavily implied that Furfur and Zepar knew the answer to the witch's epitaph and to Battler's logic error problem all along thanks to their power of love.
 * Zepar is the only character whose sprite faces the right instead of the left (other than Battler Ushiromiya's PS3 sprite). This is so Zepar and Furfur can face each other.
 * Zepar's ambiguously male nature may be a nod to the fact that some sources state the demon Zepar is based on would seduce male conjurers with pederasty.
 * The character Zepfur from When the Game Ends appears to be loosely based on Zepar and Furfur.