Ain

Biodata

Feature	Details
Name	Ain (艾恩)
Gender	Female
Affiliation	Marines; 24th Marine Training Camp 2
Occupation/Role	Marine recruit; Return-Return Fruit user 2
First Appearance	Chapter 2

Combat Profile

Measure	Documented Value	Notes
Doriki Value	401 2	Her original test result; she ranked among the three standout recruits.
Doriki Value	402 3	The later account lists her score as 402.
Combat specialization	Age manipulation and close-quarters combat	Uses the Return-Return Fruit alongside Shave.

Background / History

Ain joined the 24th Marine Training Camp at Marine Headquarters as one of its most capable recruits. Her Doriki score placed her behind Carl and Ainz, and she was identified as one of the camp’s three standout participants 2 3.

During the camp’s first training exercise, Carl manipulated Ain into activating her Return-Return Fruit while holding her hand. The ability transformed Carl into a fourteen-year-old, causing a chain reaction that disrupted the training ground. Ain accepted responsibility under Zephyr’s pressure and was assigned extra training alongside Carl 3 4.

Ain remained a disciplined trainee despite her growing frustration with Carl’s ability to avoid training. She participated in the Recruit Grand Competition, where her battle against Ainz ended in a draw because their Devil Fruit abilities directly countered each other 8 14.

During the recruits’ first field operation, Ain fought Captain Doman. After Carl healed a gunshot wound to her arm, she used the Return-Return Fruit repeatedly to reduce Doman from an adult to a child, leaving him unable to fight 18.

Ain later fought Zacur during the Hunting Knife Pirates operation. She reduced him to a powerless child and claimed his sword, Karasu, as her spoils. She gave the sword to Carl as a graduation gift on behalf of the recruits 23.

Appearance

Ain is described as a pretty, youthful-looking female Marine. Her Return-Return Fruit produces a deep pink or purplish-red glow when activated 2 3 25.

Distinguishing features:

• Youthful appearance despite her Marine experience 3.
• Deep pink or purplish-red energy associated with her Devil Fruit 3 25.
• Uses a Marine uniform and close-quarters combat techniques 8 18.

Personality

Ain is responsible and cautious with her abilities. She initially refuses Carl’s request to use the Return-Return Fruit on him because she considers it inappropriate to affect a fellow Marine, but she becomes flustered by his pleading and is ultimately tricked into activating it 3.

She takes training and Marine duty seriously, showing particular anger toward pirates who harm civilians. Her determination to capture Zacur is driven by his plundering and murder of civilians on Autumn Island 17.

Ain is also easily embarrassed by Carl’s charm and increasingly admires him. She calls him “Big Brother Carl,” defends his good nature, and becomes openly enthusiastic when praising his combat ability 12 18. Despite this affection, she remains capable of criticizing his narcissism and laziness 17 21.

Abilities & Skills

Return-Return Fruit

Ain is a Paramecia-type Return-Return Fruit user whose ability alters the age of people and objects through contact 2 3.

Applications and limits:

• Transformed Carl into a fourteen-year-old after contact 3.
• Can revert Ainz’s summoned plants back into seeds, directly countering his Shove-Shove Fruit 14.
• Reduced Captain Doman from middle age to youth and then to childhood, leaving him unable to fight 18.
• Defeated Zacur by repeatedly shrinking him until he lost the strength to resist 23.
• Reversed Zephyr’s age by ten years, restoring much of his strength and vitality 25.
• A second attempt to reverse Zephyr’s age failed, establishing that the ability could not affect him again at that time 25.
• Carl’s body required approximately three days to return to normal after Ain’s ability affected him 4.

Shave

Ain uses Shave to move rapidly during combat and evade attacks 14 18 23.

Applications:

• Dodged Ainz’s vines during the Recruit Grand Competition 14.
• Closed the distance against Captain Doman 18.
• Appeared beside Zacur before applying the Return-Return Fruit 23.

Combat Ability

Ain combines her Devil Fruit with Marine training and physical techniques. She was strong enough to rank among the top recruits in Doriki testing and later defeat experienced pirates by exploiting their age and physical weaknesses 2 18 23.

Equipment / Weapons / Items

• Karasu — A Fifty Ryo Wazamono sword taken from Zacur after Ain reduced him to a child. Ain gave it to Carl as a graduation gift 23.
• Marine weapons — Uses firearms and standard Marine equipment during field operations, including the battle against the Musket Pirates 17 18.

Relationships

• Carl — Fellow recruit and close comrade. Ain calls him “Big Brother Carl” and admires his strength, while Carl initially manipulates her Return-Return Fruit to avoid training. He later asks Zephyr not to punish her and acknowledges that she helped him discover the Holy Light Fruit 3 7 12 18.
• Zephyr — Training-camp instructor. He reprimands Ain after Carl’s staged transformation and assigns her extra training, but later accepts Carl’s request to spare her further punishment 4 7.
• Ainz — Fellow recruit and combat rival. Their Devil Fruits counter each other, producing a stalemate in the Grand Competition 14. Ain later argues with him over Karasu, refusing to let him inspect or claim the sword before giving it to Carl 23.
• Staff Officer Tsuru — Ain greatly admires Tsuru and hopes to become her subordinate after completing the internship 17.
• Doman — Pirate captain defeated by Ain after Carl healed her gunshot wound 18.
• Zacur — Hunting Knife Pirates captain. Ain defeated him by reducing him to childhood and took Karasu from him 23.

Story Role / Major Arcs

Marine Training Camp

Ain serves as one of the 24th Marine Training Camp’s strongest recruits. Her Return-Return Fruit makes her a dangerous specialist, though Carl’s manipulation of her ability causes the camp’s first major disciplinary incident 2 4.

Recruit Grand Competition

Ain’s match against Ainz becomes a prolonged ability stalemate. She repeatedly returns his summoned plants to seeds, while Ainz continually regrows them, forcing the fight to end in a draw 14.

Musket Pirates Operation

Ain confronts Captain Doman during the recruits’ first real battle. After Carl heals her injured arm, she fights without hesitation and neutralizes Doman by reversing his age until he becomes a child 18.

Hunting Knife Pirates Operation

Ain participates in the capture of the Hunting Knife Pirates and defeats Zacur with a single successful application of her age-altering ability. She later presents Karasu to Carl as a gift from the recruits 21 23.

Weevil Incident

When Edward Weevil attacks the Training Ship, Ain helps prepare Zephyr for battle by reversing his age by ten years. Her ability cannot affect Zephyr a second time, forcing the Marines to rely on Carl’s support and Zephyr’s own strength 24 25.

Trivia

• Ain’s Doriki score is recorded as 401 in one account and 402 in another 2 3.
• Her Return-Return Fruit directly counters Ainz’s Shove-Shove Fruit by reverting his summoned plants into seeds 14.
• She became responsible for Carl’s temporary transformation into a fourteen-year-old, although Carl deliberately engineered the incident 3.
• She intended to give Karasu to Carl even though he had not yet shown himself to be a swordsman 23.