In this drawing, we see a tired Greedy waking up after hearing Grandpa Gruff paying an unexpected visit into her (very tiny) apartment above her spelunking store. He found her asleep and wiped out on her sofa-bed and thought it wise to let her rest. He threw a blanket over her and began tidying up a little around her messy room and that's when she woke up. Hope you like it!
\\\~
Although Greedy owns the store downstairs, Grandpa Gruff owns the apartment above and gave it to her. In general, the elder owns a few houses around town and has given them to his older grandkids.
Living in that really small apartment just above her store, working for many hours, and being unable to cook without burning the whole kitchen — which is actually just a dresser-drawer with a hotplate, and near a miniscule, ancient refrigerator —, Greedy's eating and sleeping schedules are a mess; she hardly gets a shut-eye (which partly explains her attitude) and mostly lives on prefab food, even going as far as to skipping breakfast. Therefore, Grandpa Gruff always makes sure that she has a full and healthy breakfast, as well as enough hours of sleep. Whenever she visits Gallus and Grandpa Gruff's house, Greedy has a habit of accidentally forgetting her Wonderbolt-signed (and usually empty) lunchbox at the place, which allows Grandpa Gruff the perfect opportunity to return it to her with a homemade meal inside, the way she likes it, along with a few other things he packs in bigger bags for her (blankets, jackets, a set of toothbrushes, clean towels, moisturisers, you name it).
For her personality, as I briefly mentioned above, I believe that, at first, she was pretty crabby and grabby, and well-known for her constant demand for bits. However, she developed a warmer side after Grandpa Gruff started looking out and providing for her.
Nowadays, she asks for bits constantly, but instead of doing so out of greed, she does so because she wants to be able to provide for herself and not worry her adoptive grandfather into going through all that trouble for her. As for the way she asks for bits, it simply comes from what the old Griffon taught her. Having been taken advantage of in the early years of his life, Grandpa Gruff teaches his grandchildren to be tough, cunning, and smart, so as to show that they cannot be messed with. Although sometimes, Greedy tends to take this a little too seriously and eventually overdo it (her incident with Rainbow Dash might be a prime example).