I didn't much like Fred in some of the earlier books (he turned Ron's teddy bear into a spider, and I'm not keen on them, though I'm learning to love them through pretending to my toddler that they're nice; and he also threatened to curse Ron later: if there was a good/evil twin thing happening, I had Fred pinned as Evil. Then I read DH and fell in love with him... and she KILLED him. How unfair!)
I can imagine being a bit of a Percy, and it's not nice.