Daphne Greengrass
Most of you are aware of this girl already but here is her official introduction. She graduated from Hogwarts in 1998, Slytherin naturally, and is the potion maker at Slug and Jigger in Diagon Alley. She's really knowledgeable so she'll hook you up with whatever you need whether it's a beauty potion, something to make your hair shiny, or cure a headache or insomnia. Like most pure-blood Slyterins she's more inclined to agree with DE views and do something if they asked her but she's not a marked DE. She's kind of stayed out of the war as much as she can but she's more than happy to support her friends. Yeah, you read about her here