“Go out where exactly?”

“I see well how can I be of service to you?”

Enhanced Speed: From the Knight trait of her Queen piece, Grayfia has speed enhancement, increasing her speed. She was easily able to dodge Artemis' arrows during their fight.

Enhanced Offense and Defense: From the Rook trait of her Queen Piece, Grayfia has offensive and defensive enhancement, giving her enhanced strength and defense.

Enhanced Magic Power: From the Bishop trait of her Queen piece, Grayfia can strengthen her magic and demonic powers.

Master Magician: Grayfia is highly skilled and talented in magic, enhanced by her demonic power and Queen Piece. In Volume 4, she was entrusted to analyze the transference magic circle used by Nilrem during Khaos Brigade attack on the Three Faction leaders.

Enhanced Offense and Defense: From the Rook trait of her Queen Piece, Grayfia has offensive and defensive enhancement, giving her enhanced strength and defense

Flight: Being a Devil, Grayfia can fly using her wings.

Master Chef: As part of her maid duties, Grayfia is highly skilled in cooking.

More
Her power is stated to be on par with the Four Great Satans and even Sirzechs a Super Devil and the current Satan Lucifer is terrified of his wife when she becomes angry. In Volume 25 with the support of Asia and initially Fafnir, she was able to fight evenly against Artemis

Abilities

Immense Demonic Power: Even for an Ultimate-Class Devil, Grayfia is very powerful. She's noted by Rias and Euclid to be one of the strongest Devils produced by the Old Satan Faction and is titled the Strongest Queen.

Muse background
Grayfia Lucifuge is the wife and Queen of Sirzechs Lucifer and the mother of Millicas Gremory.She is also the older sister of Euclid Lucifuge and the sister-in-law of Rias Gremory.Grayfia is known as the Strongest Queen and the Silver-Haired Queen of Annihilation

She also does not like admitting her relationship to Sirzechs while she is "on the job", to the point of pinching Sirzechs's face if he mentions it and denying it.

Grayfia also has an issue where she becomes a "troublemaker" as stated by Azazel, who was told by Sirzechs, when she becomes drunk.

Personality

As a Devil noble and the former heiress of the Lucifuge Clan, Grayfia is very strict and serious with a calm, dignified and refined personality, with perfect etiquette.

As Sirzechs's wife and Queen, Grayfia is often exasperated by her husband.

Muse info

—— Maid of the house of Gremory

—— Strongest Queen

—— Pure Blood Devil

—— BI

—— 80% dom & 20% sub

—— From the house of Lucifuge

—— Sirzechs wife and the mother of Millicas Gremory