[quote=Krein]Charmers huh? What's the story behind them? I recognized two monster from the Gishki and Gusto families, so I'm guessing they're a team of younger monsters from other archetypes?[/quote]
*slaps Krein as hard as possible*

This was before Duel Terminal and other story stuffs. They were just sorta there. But over time, three of them have indeed grown up a little.
Wynn the Wind Charmer -> Winda, Priestess of Gusto/Daigusto Gulldos -> El Shaddoll Midrash
Eria the Water Charmer -> Gishki Ariel/Evigishki Mind Augus
Lyna the Light Charmer -> Milla the Temporal Magician

We've yet to hear back from Dharc, Aussa, and Hiita yet, though some fans compare Hiita to Laval Forest Sprite. In any event, I don't believe we have any lore on the Charmers themselves; only the archetypes they've since joined.
I remember when The Shining Darkness came out. I went with a couple friends for one of their birthdays and we each got a dozen or so packs. I pulled Lyna. I was really happy.
[s]Also got an Ultimate Rare Black-Feathered Dragon, but due to something like a bet I had to give that one up.[/s]