These are the meanings of various anime characters' names, which I've been able to find for you:
Setsuna = "a brief moment in time".
Minako = "beautiful child"
Makoto = "faithfulness; sincerity".
Ayeka = her name is taken from an old Japanese word -- "ayekanaru", meaning "delicate; frail".
Mihoshi = "beautiful star"
Ryoko = normally I would say this name means "dragon child", but sources on the web for the anime series *Tenchi Muyo* claim that the kanji for this name indicate the meaning is: "demon summoner".
Sorry, but I couldn't find anything on the meaning of "Nyago".
-- Nanaea