Book!Harry: Sarcastic, and a bit asocial. Loves his wheezy dearly. Finds Ginny immensely attractive. Likes to chill out and relax with his friends. Not an especially keen student, but still puts the work in when needed.
Fandom!Harry: Every sentence he says is a one-liner. Really good with people. Isn’t much bothered about what Ron thinks. Doesn’t seem too bothered about previously dumping Ginny (who never gets mentioned again) to start dating someone else. A complete moron when it comes to schoolwork. Can’t do anything without Hermione.
Book!Ron: Sweetie-pie and cinnamon roll. Will punch anyone who insults his friends. Very funny, but also brave, emotionally-observant, and kind. Loves Hermione and Harry dearly. Incredibly loyal, and defends the oppressed. The best friend anyone could ever have.
Fandom!Ron: A bit of a moron. Rubbish at schoolwork without Hermione. Isn’t that close with Harry, who largely keeps him around out of pity. Eats too much. Not an especially good friend. Says lame jokes, and hides in the corner when things get bad. Probably has more teeth than brain-cells. Will likely end up with Blaise because all their other friends have paired off.
Book!Hermione: Emotionally insensitive, but loyal and kind. Has a massive crush on Ron, and finds his kindness incredibly attractive. Sees Harry as a little brother. Has a tendency to be smug, but this is mitigated by her natural insecurity about failing. Is not confident about romance at all, and instead spent at least four books pining over her redheaded best friend. Most people find her annoying, aside from her close circle of friends. Gets along with barely two women her own age.
Fandom!Hermione: Brilliant at everything for no reason. Knows that she’s brilliant at everything, and will take no prisoners. Is not that interested in Ron, and -in certain timelines- has conventionally broken up with him a few months before, and now sees him as a goofy platonic friend who she just finds annoying. Is randomly attracted to someone who used to wish death upon her or someone else who used to bully her over her looks. Harry’s relationship counsellor who he is really close with. Is either strictly heterosexual or very gay (either way, she is adored by all her fellow students). Is the leader of a gang of girls at Hogwarts, and is adored by all other women she meets.
Book!M*lf*y: A pureblood supremacist who sees muggle-borns as less than human. Doesn’t have friends so much as has lackeys to do his dirty work. Thinks he’s a bigger deal than he actually is. Only gets good marks in Potions due to favouritism.
Fandom!M*lf*y: Snarky sarcastic pretty-boy who will inevitably start snogging either or both the two Hs for seemingly no reason. Is basically a richer, more confident version of book!Ron. A rival for Harry, and a Potions prodigy to boot. Wears really nice clothing, with the exception of the obligatory leather trousers. Is either incredibly gay, or emblematic of non-toxic heterosexual masculinity, depending on which H the author is pairing him with.
Book!P*nsy: A bully who racially abuses POC Hogwarts students. Follows M*lfoy around because he likes her being vapid towards him. Tried to sell Harry out to Voldemort, and bullied Hermione about her physical appearance.
Fandom!P*nsy: An attractive, witty young woman with a sharp mind. Either M*lf*y’s straight BFF or his very gay BFF. Owns her sexuality, and takes no cr*p from no one about it. Someone manages to make Hogwarts robes look fashionable. Will start snogging the other H that M*lfoy isn’t snogging (it’s usually Hermione).
Book!Bl*ise: His mum is rich? He’s physically attractive and a little vain? Honestly, this is all I could find; he only really appears in HBP for a couple of scenes.
Fandom!Bl*ise: Very attractive, and has probably snogged (or done more) with most of the girls/boys in his age group at Hogwarts. Will likely end up with Ron because the other two people in both their trios have started snogging, so why not?
[Not gonna go into Ginny, Neville and Luna’s portrayals, because -mercifully- they seem to have been left largely unscathed by this]