Sailor Neptune at the end of her transformation, arms folded and head tilted, standing in a starry blue-green sky among pale crystal shards.
Sailor Neptune, bust.

Sailor Neptune

“Neptune Planet Power, Make Up!”

japanese name
Kaiou Michiru (海王みちる)
90’s english dub
Michelle Kaioh
name meaning
the sea king’s full tide
likes
painting, violin, swimming, the sea
dislikes
sea cucumbers
birthday
march 6
zodiac sun sign
Pisces
blood type
O
Takeuchi colour illustration of Sailor Neptune against black, looking back over her shoulder with the Deep Aqua Mirror in her hand and her planet small above

Michiru Kaiou is a world-class violinist and a painter whose canvases sell, wealthy and always composed. Her family name, 海王 (Kaiou), is written “sea king”, and 海王星 (Kaiousei), the sea-king star, is the Japanese name of the planet Neptune. Her given name, みちる (Michiru), can mean to rise or grow full, as a tide rises to the flood. She loves Haruka, Sailor Uranus, and through her art what is coming reaches her first.

Under Michiru’s calm is a soldier as hard as Haruka. She accepted the mission first and drew Haruka in after her, and she will spend innocents, and herself, to guard the whole. Her talisman, the Deep Aqua Mirror, always shows the truth.

read the Neptune page →← back to character select

in modern astrology

significations

Michiru seated on a windowsill holding Haruka’s hands, the misted city and both of their reflections in the glass behind them
compassion
the other one’s trouble, landing as yoursThe warmest thing modern astrology gives Neptune, and it runs on the same softening everything else here does, turned toward another person. When the edge between you and someone else goes, their situation stops being information and starts being something felt.It shows up as reading a room before anyone has spoken, as being moved by a stranger’s trouble out of all proportion to one’s stake in it, and as the difficulty of putting down what was only ever picked up by accident.
Michiru at an easel painting a vase of red roses from life, watched from behind by someone out of focus in the foreground
imagination
fantasy, inspiration, the picture firstModern astrology hands Neptune the imagination and calls it the higher octave of Venus: art met by immersion rather than by judgement. Where Venus likes a thing, Neptune disappears into it.It shows up as music and image and reverie, and as the knack for picturing what is not there yet, which is the same faculty that makes a person easy to lead somewhere that does not exist.
Michiru’s face reflected in the Deep Aqua Mirror, held up in her own hand
delusion
confusion, and believing the pictureThe dark end of the modern list. An illusion is a likeness that convinces; delusion is the point where the likeness is taken for the thing itself. Confusion is the same failure in a milder form: with no edge between what is and what is wished for, there is nothing to check an impression against.It shows up as a wish or a fear mistaken for a fact, as a certainty that does not survive daylight, and as a fog a person cannot say when they entered.
Sailor Neptune playing her violin with her eyes closed, lit from behind
mysticism
faith, and the self going quietJupiter is belief: doctrine, scripture, the institution, the law that can be stated and taught and argued over. Neptune is faith, which is the part that dissolves the structure. The moderns give it the mystic, the medium, and the vanishing of the self.It shows up as a practice that empties rather than fills, as devotion with no argument behind it, and as something that happened which the person afterwards cannot put into words and will not stop trying to.
Sailor Neptune with her planet, drawn by Naoko Takeuchi

neptune at a glance

modern rule
Pisces, a modern reassignment
Pisces’s traditional ruler
Jupiter
sect
none: outside the old system
Neptune across the zodiac, on a Cancer rising wheel: modern astrology gives it Pisces, and no other signAriesTaurusGeminiCancerLeoVirgoLibraScorpioSagittariusCapricornAquariusPisces

trans-saturnian

Neptune isn’t one of the seven planets Hellenistic astrology reads. Those are the lights you can follow by eye, from the Moon out to Saturn, and they’re what two thousand years of that writing was about. Neptune was only found in 1846, so it was never in anyone’s sky while the tradition was being written.

Modern astrology gave it Pisces, Michiru’s own Sun sign, which the tradition gives to Jupiter. That is the pattern rather than the exception: the moderns didn’t find new meanings past the edge of the old sky so much as move meanings that already had an owner. This site reads the outer three as generational rather than personal, and leaves the rulerships where the tradition put them. When one of them does come to a placement, though, it is felt as hard as any of the seven.

the trans-saturnians →

the seven traditional planets →

Sailor Neptune holding up the glowing Deep Aqua Mirror beside her green planet and its ring, from the 90s anime

powers and transformations

  • Pixel sprite of Sailor Neptune’s transformation wand.
    The Transformation Wand

    Her transformation wand. In the anime she raises it and calls “Neptune Planet Power, Make Up”. In the manga’s Dream arc her power comes from her own Neptune Crystal instead, and the call becomes “Neptune Crystal Power, Make Up”.

  • Pixel sprite of the Deep Aqua Mirror, a gold hand mirror with a pale rainbow glass.
    The Deep Aqua Mirror

    One of the three talismans, with Uranus’s Space Sword and Pluto’s Garnet Orb, and it always shows the truth. In the manga it’s her own hand mirror from the start. In the anime she only gets it when it comes out of her pure heart, which is when she’s revealed as a talisman bearer. Submarine Reflection is fired from it.

what she can do

    She isn’t in this arc. Michiru’s first appearance in the classic anime is in Sailor Moon S.

      She isn’t in this arc. Michiru’s first appearance in the classic anime is in Sailor Moon S.

      • Neptune Planet Power, Make Uptransformation
      • Deep Submergeattack

        Her signature attack.

      • Submarine Reflectionattack

        Fired from the Deep Aqua Mirror.

        She isn’t in this season of the anime.

        • Super Sailor Neptunetransformation

          In episode 167 she’s given new power and the name Super Sailor Neptune.

        • Galactica Planet Attackattack

          Wearing Galaxia’s bracelets, she and the other guardians Galaxia controls attack together.

        variations

        Labelled by source. The manga is the primary text here. The anime, Crystal and the live-action series are separate continuities that sometimes disagree, and where they do, this site argues from the manga.

        • manga

          Sailor Neptune

          Act 27, Infinity
        • manga

          Super Sailor Neptune

          Dream arc
        • manga

          Eternal Sailor Neptune

          Stars arc
        • manga

          Princess Neptune

          Silver Millennium
        • anime

          Sailor Neptune

          Sailor Moon S
        • anime

          Super Sailor Neptune

          SuperS onward
        • crystal

          Sailor Neptune

          Season 3
        • pgsm

          does not appear

        elsewhere

        Crystal

        Season 3 covers the Death Busters and follows the manga closely, designs included. Anyone who has read the Infinity arc will find very little here to surprise them, which is the point of Crystal.

        the English dubs

        Michiru becomes Michelle Kaioh. The Cloverway dub of Sailor Moon S rewrote her and Haruka as very close cousins to remove the relationship, and the result is a show in which two cousins act like a couple and nobody comments. The dub also gives her an ex-boyfriend called Mike in episode 107, who does not exist in Japanese.

        Irwin released Outer Guardian dolls in 1998, ahead of the season airing in North America, and printed a third civilian name on the box, Nerissa. It is Greek for sea nymph and is also a character in The Merchant of Venice. The name appears nowhere else.

        Sera Myu

        Neptune has been in the musicals since the outer guardians entered the stage canon, and the stage versions keep the relationship intact.

        live action

        Pretty Guardian Sailor Moon, the 2003 live-action series, runs only through the Dark Kingdom arc. The outer guardians never appear, so there is no live-action Michiru.

        in development

        Takeuchi built Neptune and Uranus together, after the inner guardians were already established, as complementary opposites meant to work alongside Pluto from the start. Early concept art had both of them affiliated with the Takarazuka Revue, and Michiru wearing a bow in her hair at school. Neither idea was kept. The Materials Collection gives her kindness “as great as the sea”. Takeuchi has joked that the wave in her hair might be read as seaweed.

        last updated july 30, 2026 · rebuilt from the wiki

        Sailor Moon, its characters and all original illustrations are the creation and property of Naoko Takeuchi, first published by Kodansha; the animation is Toei's and the game sprites are Bandai's. This is a non-commercial fan page. Art appears here to identify the characters it discusses and to illustrate commentary about astrology, which is believed to be fair use. No ownership is claimed, and nothing here is licensed, endorsed or affiliated. Pixel art for Helios, the Asteroid Senshi and the Starlights is from the fan project Sailor Moon ES RPG by sawaii (sawaii.wixsite.com/smesrpg), used with thanks.

        ✦ junk drawer

        things in here:0002

        odds & ends. old graphics, for fun.

        • Takeuchi manga panel of Michiru seated holding the Deep Aqua Mirror, Haruka behind her with both arms around her and her eyes closed