| Name: | Suiko Kaiou |
| Meaning: | Water Girl of the Sea Ruler |
| Mother: | Mrs Hokori Nozomi (Sailor Neptune's mother) |
| Father: | Dr. Tsuguri Kaiou (Sailor Neptune's father) |
| Birthdate: | February 29 (Pisces) |
Physical Description:
| Hair Color: | Aqua Green |
| Eye Color: | Sky blue |
| Hairstyle: | Wavy hair she wears in two pig tails. |
| Sailor Suit: | Blue and aquamarine, uses boots as former Uranus (Haruka gave them to her.). |
| Best Friend: | Nintai Tomoe, Haruka Ten’ou, Kinpatsu Ten’ou |
| Love Interest: | Kinpatsu Ten’ou |
| Favorite Food: | Lasagna |
| Strenghts: | Singing |
| Likes: | Playing keyboard, swimming |
| Weakness: | Housekeeping |
| Dislikes: | Been compared with Michiru |
Suiko’s father died before she was born and her mother passed away few years after. They were old. She was raised by her sister Michiru and her lover Haruka. She developed a crush for Haruka and she had an eating disorder in her teen age. Finally, she met Haruka’s nephew and found a new love. She is part of a music band with Kin-kun and Megu Gingekko. Nintai is a role model for her and they are very close.
| Weapon 1: | Neptune Aqua Mirror |
| Attack 1: | Ocean Marineblau Tide! She throws a huge wave. |