Setsuna rules so much more in the manga.
She's still mysterious, but more is learned
about her.

Manga 4
Act 16- There's a small little flashback with
Pluto saying "That is the charm that will
bring you fun" This isn't her official intro

Manga 5
Act 18- This act is definately when Pluto is
officially introduced. You first hear about her
when Luna is dreaming. Serenity talks to
Luna is her dream and talks about Pluto.
She's the solitary guardian who protects the
closed door. A bit later in the act, ChibiUsa
wants