This section contains plot details of Ys IX: Monstrum Nox.
Do not read it if you have not played the game and intend to play the game in the future.
Aprilis (アプリリス) is a hooded woman with determined eyes and an artificial arm and leg whom Adol encounters during his breaking out of Balduq Prison. She turns Adol into a Monstrum and forces him to fight demons in the Grimwald Nox along with other Monstrums. She tells Adol to investigate the mysteries behind the prison city if he wishes to find out the truth behind the Grimwald Nox and break its curse.
Come forth, my Monstrums! And consume this dark night!
Aprilis appears as a young woman with black hair and blue eyes. Her left arm and leg are prosthetic limbs, and her right arm is covered with scars. She wears a black hood and cloak, a fingerless black glove, and a golden belt around her waist. She carries a flintlock pistol, a dagger, and the Lantern of Crossing.
As Saint Rosvita, she wears a silver armor and wields a great sword.
Aprilis is a cold and dignified woman, her years of seeing her comrades die repeatedly has made her abrasive. She mostly focuses on protecting Balduq by taking care of Lemures and the Grimwald Nox, and tends to spend time by herself on top of the Ruined Belfry in the Central District. As she spends more time with Adol and the Monstrums, she begins caring for them more, often defending them herself.
At a time when Aprilis was still known as Rosvita, she grew up in a modest village with her doll, Anemona. She lead a peaceful life there until the day she nearly died pulling a drowning child from a river. That's when Rosvita met the King of Gods, who saved her life, and in exchange imparted a mission onto her — expelling Britai's army, the forces of the god Luki. The ongoing war between Gllia and Britai was dominated for the longest time by the latter.
To realize her mission, Rosvita volunteered for the Gllian army, where she met her companions. Rosvita managed to turn the tide into the Gllian army's favor, take back Balduq and lead Gllia to victory. After a hundred years of war, Britai no longer had the morale to continue their losing battle. It was at this time where the gods Grimnir and Luki were both slain upon the other's blade. This war came to be known as the Hundred Years' War, and during the chaos of its aftermath, Rosvita was deceived by the king of Britai, and sentenced to death by burning.
She is the historical figure of Balduq, Saint Rosvita, who fought in the Hundred Years' War over 500 years ago. After the war, she was framed and burned at the stake by the Gllia royal family, who was jealous of her achievements. Aprilis is a homunculus clone of Rosvita, created by Zola in his alchemy experiments that were performed in order to revive Rosvita. All Monstrums except Doll and Adol are homunculi clones of Rosvita's comrades, who fought alongside her during the war.
She and the other Monstrums were given the power to fight in the Grimwald Nox, in place of the gods fallen in the Hundred Years' War. However, around 8 years ago, Zola disappeared without notice in search of a way to permanently break Aprilis and the Monstrums from this responsibility. Without Zola, Aprilis found it difficult to raise Credo, Krysha, Yufa, and Jules when they were kids. So she faked their identities and pretended they were war orphans to be adopted. When they became old enough to join the fight in the Grimwald Nox, she sought them out and activated their power by shooting them with an alchemy bullet, turning them into Monstrums.
Aprilis's musical theme is called "Aprilis", continuing the Ys tradition of featuring a musical track named after the respective game's heroine. In Ys IX, the track "Alchemy Lab" contains a motif of Aprilis' theme.
In the Ys IX Super Ultimate album, "Aprilis" received an arrangement by Yukihiro Jindo.
- Rosvita is based on Joan of Arc due to similarities in their backstories, and her name is a reference to Hrotsvitha.
- She is one of the few characters to have more than one raid skills in a single game. Even among these characters, she is the only one to have three raid skills.
- Aprilis carries a dagger that she never uses throughout Ys IX.