Airi is my favourite of Queensblade as well, followed by Nanael, both of them are rivals and are super cute lol
Airi is called 'Infernal Temptress Airi', but that's only half the true meaning of her title. If I put her title in another way closer to her Japanese title, its: 'Meido Temptress Airi'.
Yes Meido as most people know is 'Maid', which is what Airi is. But Meido in Japanese Kanji is a pun itself, it means 'Hell' or 'Hades'. So, Airi's title is a double meaning, she is a temptress maid from hell, a super cute one lol. Her master from hell sent her to the fight in place of him or something. Her weapon is a scythe.
In the trailer, you see her revealing her underwear, that's actually her 'invisibility' ability, which aways fails, by only turning her clothes invisible lol
That's Airi, Nanael herself is also super cute. She hates female humans, but loves male humans, she thinks they're very interesting lol
Nanael is incredibly ecchi to behold lol, because of the capless bottle of 'Heavenly Milk' she carries around with her. Everytime she gets hit, her flimsy dress gets shreds to pieces and the milk is spilt all over her, you should get the picture
She's very cute because she's a very unattentive fighter, because her sword fights on its own, she doesn't need to care. So while the sword is fighting, she puts on specs and read a book, yawns or does some manicure lol. She's really great to look at lol
Airi comes from Hell and Nanael comes from Heaven, so they're naturally rivals. Can't wait to see their catfight in the anime.