That's easy Ginny. She's the maintank, or offtank, but that doesn't mean she's a guild officer, or guild leader. Whoever is in charge in her guild is all like "ZOMG BOOBIES" over the two girls posting slutty pictures on her guild forums. And if she let them die, and they start crying, the GM/Officers get's pissed off at her and tells her to tank better. The guild sluts use their position, as a means to play the guild leadership against Marigold because she's not "one of them".
Classic guild drama.
Sounds like Marigold needs to grow a bit of a spine, and find herself a new guild. Boobie favoritism is the worst kind of favoritism.