>>2283I've been researching Aunt Marge for several years now, so I would like to take this opportunity to consolidate many of my findings and give you guys a little update.
Little is known of her background, but it's apparent that every encounter Harry has had with Marge has been entirely unpleasant. For example, on one occasion she whacked Harry on the legs with her walking stick when he kept beating Dudley at a game of musical chairs. What's intriguing about this is the implication that Aunt Marge uses a walking stick - most likely due to her obesity. In 'Flight of the Fat Lady' however, it's not mentioned whether or not she is still using one. This may be because the author is expecting the reader to assume she is still using one, or that her use of a walking stick was only temporary.
Aunt Marge breeds dogs in the countryside, and has high standards when doing business. For example, when a dog of hers gives birth to a mongrel, she drowns it (and rightfully so) so that it won't reflect badly on her other assets. In addition to this, she has built relations with other people outside of her business and family, notably Colonel Fubster (whom she has a personal relationship with).
Aunt Marge is a large, beefy woman with a mustache (possibly Colonel Fubster's type), showing that she shares many physical traits of her brother, Vernon. She also shares many of his beliefs as well, notably her support for corporal punishment (which, after Harry's numerous unreasonably outbursts at his friends, is very much justified).
It's made very clear that the Fat Lady is unaware of Harry's abilities, yet decides to torment him anyway. Unlike Vernon (who prefers to keep Harry out of sight), she demands he be kept an eye on since he's not to be trusted. What's interesting about this is that her will seems to trump Vernon's despite it being his house. They very much do resemble each other, but it's possible she ups him in viciousness and cruelty (let alone fatness).
Marjorie's relationship with Petunia is rather curious: she utterly resents Harry for inexplicable reasons but is quick to apologize, albeit half-heartedly, to Petunia when she starts rambling about Lily. The Fat Lady probably respects Petunia due to her relationship with Vernon, but it's never clarified. I can imagine Petunia usually remained quieter than usual around Marge due to her abrasive personality, but we can't be sure.
One evening, during her stay in Little Whinging, Aunt Marge gets drunk and begins insulting Harry's parents right in front of them. Harry loses his temper and then all Hell breaks loose. Aunt Marge gets blowed and becomes airborne, floats out the door and into the evening sky - to the sheer horror of Vernon and the peculiar apathy of Petunia and Dudley.
Cornelius Fudge later informs Harry that Aunt Marge was found circling a chimney stack just south of Sheffield. Now, the distance between Surrey and Sheffield is roughly 180 miles, but we could narrow it down to around 150 as that is the distance as the crow flies. He does state it was just south, so we could probably cut off about 10 miles. The speed at which the she flies would be equivalent to the wind, which would probably be around about 13mph given that it's late summer when this event takes place. This would mean that the flight of the fat lady must have lasted around about 13.08 hours. This of course is ridiculous because we know she was punctured way before then, so either Fudge meant they found way south of Sheffield or wind speeds were much greater than average.
We never see Aunt Marge again after she is punctured and has her memory modified, but it can be assumed that she still recalls who Harry is despite having no recollection of the incident. It's a real shame we don't get to see more of this fascinating character.
I would also like to take a moment to analyze Harry blowing her in this video:
https://www.youtube.com/watch?v=0_KQ1Uwvxn0At around 1:53 she starts blowing, but I would say is still <1% blow.
1:58 she blows harder to I'd say at least 1 or 2%
At about 2:10 Harry has blown her so much her necklace flies off, making her about 15 or even 20% blow.
2:15 she blows faster and reaches around 50% in my estimates.
2:28 she starts rising off the ground with the chair still stuck to her ass, as her feet are dangling above the ground (take note of this). At this point she is about 80% blow.
2:35 Petunia gets up and rushes to a corner, revealing that Aunt Marge's feet are back on the ground again.
2:44 her last button pops off shortly after the chair breaks, making her around 99% blow
3:25 she is outside and is sailing away, on her way to Sheffield, at which point I'd say she is 100% blow.
For those of you interested in what I look like, or would like to see some more analysis of Aunt Marge, here is a video I made on the subject a while back:
https://www.youtube.com/watch?v=XfCQLadQbXw&t=112s