My heart bleeds for the lop. Sounds like the lop is doing what any rabbit in a cage might do -- the lop is being overly territorial about it. I would love to see what would happen with this lop's personality if you would bring the hutch in, leave the door open in a well-traveled part of the house, and let her feel more a part of the family. I wonder if you wouldn't benefit from reading this wonderful article on bunny language:
http://language.rabbitspeak.com/rabbittalk.html
I feel that you probably would do well to continue educating yourself about rabbits before starting in with a baby Flemish. I say this as someone who had a multiple-rabbit household long before getting into Flemish Giants. Remember, a lot of the kit's basic orientation toward socializing with humans is settled long before you get the rabbit from the breeder. You should first work on selecting a breeder and learn from them how much they are handling the rabbit during the 10 weeks before you get them. Is the breeder holding each rabbit in the litter each day to ensure that the kits are optimally exposed to humans? A good place to find a breeder for Flemish Giants is on the website for the National Federation of Flemish Giant Rabbit Breeders. Most breeders that I have ever met, and I am admittedly new to the breeding and show side of things, do not breed for pet quality animals. They breed for show quality. Probably what they will offer you is a rabbit that they don't think will fare particularly well on the show tables. Not all rabbits who aren't show quality necessarily have the personality traits to be good pet bunnies. If you do get to know your breeder in advance, you may be able to visit the litter several times before the kits are weaned so that you too get a sense of the beahvior of specific kits.
The advice about spaying and neutering above is right on. Rabbits can become more accustomed to each other more readily when they don't have the distractions of high-raging hormones. I did not appreciate this enough but learned the hard way. I brought Maddie home as a rescue -- she wasn't yet spayed and was just about 1 year old. I didn't watch her closely enough while introducing her to Dorcas and Jemimah. She and Dorcas got into a fight that I didn't break up in time. Maddie bit the tip of Dorcas' nose off. This greatly hurt Dorcas and I wasn't very happy about the vet bill I needed to pay for Dorcas' "nose job". Once Maddie was spayed, there was no problem in her getting along with Dorcas and Jemimah.
Now, Dorcas and Jemimah were littermates, and there's some interesting lessons there. I had them spayed as soon as I got them because I had a non-neutered male at home already. Dorcas and Jemimah got along with the buck from the moment they met him. The problem was that long after they had been spayed, Jemimah, who had previously been smaller than Dorcas, grew up to be quite a bit larger than Dorcas. The tables had in their minds to be turned. Although they had gotten along fine for months, one day I heard loud screeching and thumping from the living room over my head. Dorcas and Jemimah were charging each other, meeting in the middle of the room, holding onto each other with their front paws and trying to eviscerate each other with the back paws. Each came away from the encounter with a little wound. I had to keep them separated for a couple of weeks and then reintroduce them. For years after that, they got along just fine. . .
Then, when they were six, we got our second Flemish Giant buck (the first one died an untimely death from a surgery for a broken leg gone wrong). Suddenly, Jemimah and Maddie started picking on Dorcas, who is the smallest of the rabbits. They routinely chased her around the rabbit room, pulling tufts of hair out of her bottom and actually biting her sometimes. This all seemed to be in response to the introduction of a new rabbit into the mix. I removed Dorcas from the group and several times have tried reintroducing her, but her littermate sister Jemimah is the one who immediately attacks her on first sight. Dorcas has become an "only" bunny in a different location in the house.
Anyway, this is quite a long entry I realize. I apologize for being so long in words, but based on experience, I think the strategy of getting littermates and raising them together does not necessarily mean they will get along together. Rabbit social dynamics can be very complex.