First Appearance On the Windy Planet
Voice Actor
Japanese Voice Actor Haruka Kudō


Gender Female
Age 17
Height Unknown
Weight Unknown
Affiliations Planetary Gears
Setsuna (セツナ Setsuna?) is the Designer Child that plays host to the Planetary Gear known as Siren. She is the 7th member introduced and the last to awaken, assuming the leadership of the Planetary Gears upon her reawakening due to being part of the royal family.

Like Hana Mutou's pet Pitz, Setsuna is accompanied by her pet squirrel, Lappa.


Setsuna is mostly a fair skinned petite girl with light purple messy hair and deep purple eyes. Currently she wears a long dark purple flowing dress with a ribbon on her chest and a hat. She also wears a pair of purple boots.


Setsuna was a lively and happy teenager. She enjoyed swimming and watching the environment through her window and was grateful for Mao Marimura for taking care of her. However upon learning of her true motives, she becomes more reclusive, believing that getting to know people deeply was scary and that it would only hurt oneself. 

Upon her reawakening Setsuna is more direct and speaks with a more serious tone, expressing her authority over the rest of the Planetary Gears. Although she still prioritizes their main objective, she does not seem to show any arrogance or superiority over humans like her comrades and even shows traits of questioning their goal, seeing how she felt disgusted at being used by Mao, but noticing how they would likewise use humans for their own ends.

Despite the fact she leads the Planetary Gears, she tends to act in a more supportive way and as a voice of reason of her comrades, rather than a leader.

Skills & AbilitiesEdit

Setsuna has shown to have the ability to manipulate Orgone energy when she sings similar to Hana because of this ability it is likely that she is part of the Planetary Gears royal family. Setsuna is physically fit being able to swim 1,200 meters a day.



Trivia Edit

  • Setsuna's name could be a reference to Gundam 00's Setsuna F. Seiei.


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