Rumi Aikawa (相川 留美, Aikawa Rumi) is a support character from the Metal Slug series.
Rumi's primary intention of joining the Regular Army is because of her mother diagnosed with a heart condition as well as her older sister, Madoka, who was physically weak, so that both of them can make use of the Regular Army's medical facilities for treatment.
During her training, she was accidentally shipped to the frontlines after a paperwork fiasco and, despite the fact that her training was not yet completed, she manages to escape fighting unscathed and without capture.
After the first conflict with the Rebellion, Rumi is given a chance to resign from her position, and carry out the rest of her life as a civilian. She declines the offer and transfers into the Regular Army's Intelligence Division.
As a supply sergeant, she packs an incredible amount of cargo into her backpack and tries to deliver them to the friendly forces, out in the battlefield, in hopes to help them win. However she has a horrible sense of direction, and often gets lost. This results in her appearing out of nowhere, and vanishing without a trace, gaining her the nickname "The Wandering Ghost" by other soldiers.
Her sister, Madoka, also appeared to have joined the military but in a bid to be more fit. Like her sister though, she too has been thrown to the frontlines by problematic paperwork, and often wanders off within the battlefield.
Rumi is also known to talk incessantly, and has been known to occasionally sass back to superior officers. Her favorite quote is "Hmph!". She was also seen piloting a Hi-Do copter on Metal Slug 3D and Metal Slug 7 and XX
Rumi is a young woman with blue eyes and blonde hair in a ponytail. She wears green wrist bands, a white buttoned T-shirt tucked into a green pair of shorts with a black belt, white socks rolled up to her knees and green boots.
Unlike other POWs, Rumi is not found tied up, rather just mindlessly wandering around. Tagging Rumi will cause her to fall on the ground, dropping whatever item she's holding, and flee after a salute. If Rumi walks enough steps without being tagged, then she'll drop the item and run away by herself, forfeiting a POW bonus. The player is able to shoot her backpack for more items at the expense of making her walk faster.
In Mission 24 of 2nd Mission, Rumi can be found hidden inside a small room that is accessed by doing a Metal Slug Attack on a specific gap; she gives the E-Armor to the player. Rumi can be only be rescued if Red Eye completes Mission 22 with the Slug Flyer intact. Every other route puts Red Eye in the final stretch of Mission 24 rather than in the beginning (Tequlia always starts from the beginning).
In Other Games
Rumi becomes a more prevalent character, showing up in cutscenes and working as mission control for Marco and company. Rumi also gives the player access to the Garage, where they are able to modify their Slug to be deployed in missions.
In this game, Rumi slowly supplies Action Points (or AP) to deploy units. At every specific threshold, her icon turns from red to green allowing the player to level her up. The rate of AP supplied goes faster and more AP can be held (up to 9999 AP) as the level increases. At level 10 (MAX), Rumi stops walking and stands still at a salute. When a new mission starts, Rumi starts back to level 0.
The player is able to increase the AP supply speed and limit permanently by paying MSP per level up.
Rumi has various animations from what action is occurring on-screen. She trips when the player levels her up, salutes when the player wins and runs away from a loss.
Rumi works the same way as in Metal Slug Defense, with the cap now increased to 99999 AP.
Rumi becomes a playable unit in the "Amadeus Revenge" event as a Box Crank unit, complete with new animations. While she doesn't seem like a competent fighter, with her close range attack being a nervous flailing of her arms, she has strong arm strength, able to toss multiple grenades at once from afar.
Her special revolves calling the Regular Army Helicopter and throwing items onto the the battlefield while in the air. The items can be picked by the player's units, with the Heavy Machine Gun temporarily increasing attack strength and Bomb Crates instantly recharging a unit's special. A unit cannot pick up another item if their attack bonus or their glow are still active. These items will eventually disappear if not picked up.