They are all pretty terrible so it is hard to decide! I have also read some terrible Voldie/Bellatrix fics where Voldemort is all sweet and sensitive, and Bellatrix totally loses her insane personality because she is so in love with him. Yuck! haha
Cool! I have never played her before, but that's mostly because I am just now getting back into RP after not doing any at all for a couple of years.