Set after the anime, a chance encounter with a woman at a gay bar has Sei confused about several things. Metamorphosis is a Sei-centric fic that explores the relationships characters have with one another, as well as the ambiguity of soeur relationships. It's predominantly a Sei/Yumi, Yumi/Sachiko, and Sei/Alice fic.
This fanfic provides examples of:
- Continuation: Metamorphosis is set after the anime ends.
- Gaydar: Sei mentions that she could tell Yumi was lesbian virtually from the first time they met.
- Polyamory: Metamorphosis ends with a relationship between Sei, Yumi, and Alice.
- Sei makes an Alice Allusion in the second chapter.
- Sei tells Alice that her mother's nickname for her, "Kin-kun", sounds a lot "King Kong".
- Situational Sexuality: Subverted. Sei mentions that the all-girls high school she went to didn't have too many queer girls (or at least openly so). Most girls were into just PseudoRomantic Friendships.
- Unsettling Gender-Reveal: Sei is surprised in chapter 1 when she notices something different about the girl she's kissing. It turns out that Alice is transgender.