@Ammokkx
Just a question I wanted answer, knowing that Ethel would not duel anyone below Earth would she make an exception if she knew one of them was the sister of a professional duelist who is in Light?
Well, let me rephrase it.
She wouldn't refuse a challenge of them, but her own pride would never let herself challenge one themselves. It's a two way thing; Refusing a challenge from them would seem like she's afraid, but challenging them herself would be cowardly and it's not like she'd learn anything out of it.
She's like a pre-character development, Manjoume/Chazz, she thinks she's the biggest hotshot since Yugi but isn't as good as she thinks she is. She's good, just not that good.