I think they were late season characters. They were "Sailor Scouts" named after the moons of Jupiter or something like that. Their secret identities were that of "pretty boys".
The Starlights were (in the anime) male rock stars that transformed into women to fight against evil. They first appear in episode 173 of the anime series. They come from the planet Kinmoku, which has been destroyed, and disguise themselves as male pop stars (The Three Lights) in order to hide their true identities as they search for their lost princess, Kakyuu. The black-haired one (Seiya) also is in love with Sailor Moon.
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