Rose used "empathy" and "I" in the same sentence without a negator? Can you say "chutzpah"? Oh, she's talking about animal empathy. Not sure she'd be capable of comprehending what most of us mean by empathy.

"Foul is Rose"
To the tune of "Fair is Rose" from Gilbert and Sullivan's Ruddigore
CHORUS:
Foul is Rose as rot and death!
Colder her heart than Titan's lakes!
Toxic is Rose as nundu breath!
Rose is a vicious little snake!
Oh, Rose Potter, off to Mount Etna go!
That amulet take and jump in a lava flow!

1ST AGENT:
Some five and a half tales, this "druidess"
A jailbait preteen villainess
Has made a mess out of canon 'verse.
And there is even worse:
Bullies her "friends" as a matter of course
And murders without any remorse!
And one thing more, oh not-dear Rose
Go and put on some clothes!

CHORUS:
Oh, Rose Potter, go throw yourself away!
Is anybody going to call you out today!

RENA:
Know, Rose, the laugh isn't be on your side.
You are going to die!

2ND AGENT:
Foul is Rose as any skunk's spray!
Colder her heart than helium streams!
Toxic is Rose as curare!
Rose is a very dreadful dream!
Oh, Rose Potter, heroic you are not!
All your compassion doesn't even rate a single dot!
Foul is Rose.
Vile is Rose.
Ro-o-o-ose is a vicious little snake.

Before I say anything further, let me say congratulations on sporking another Rose Potter "book". If Bleeptea were a thing IRL, I'd suggest drinking copious amounts of it.

Actually, normal IRL tea can be calming as well, so I suggest taking a nice, slow drink of a cup or two before going any further!

That said, off to the mission itself!

First off, (at the risk of tooting my own horn) an internal squee rose up when you mentioned greengrocer's apostrophes, for reasons that you might be able to guess.

But a few errors as well:
* That sounded suspiciously like the Ground type one-hit K.O. move.
"Ground-type" should be hyphenated.

* "I trust your judgement, all right?"
The word is spelled "judgment", that is to say, please remove that first "E".
(I'm pretty sure that I'll get some flak for this from our friends across the pond.)

* Riddle accused Hagrid of opening the Chamber of Secrets, and suddenly cast an Arania Exhime at the acromantula when it tried to escape.

...

“It’s spelled E-X-U-M-A-I,” Rina explained....
If the incantation was misspelled, then I'd suggest putting it in quotation marks, like you did with Rose's faux-Latin back in the first part.

* “Get out, uncanon influence!” she yelled, whacking Aragog again, “begone, bad characterization! The power of Rowling compels you!

The punctuation is off. Since there's an exclamation point to end the first quote, the second quote should start with a capital letter. Otherwise, replace that first exclamation point with a comma.

In other words, fix it like this:
"Get out, uncanon influence," she yelled, whacking Aragog again, "begone, bad characterization!"

Or like this:
“Get out, uncanon influence!” she yelled, whacking Aragog again. “Begone, bad characterization! The power of Rowling compels you!

* And speaking of the exorcism, three questions:
1) What happened to the wraith itself? Usually an exorcism features the wraith leaving the body, even if it's only one sentence.

2) Why did Rina have to use Expelliarmus? She seemed to be doing the traditional "whack 'em on the head with canon" method with no problems.

3) How did Rina use Expelliarmus/i>? Unless Rina is able to do wandless magic, the omission of her taking out her wand (which is mentioned later in the mission) can be jarring.

Whew, that was quite a bit of typing. But nothing compared to what you have to deal with! Good luck, and don't go too insane!

I had no idea it was even possible to mess up canon that badly. Nice mission though.

(Also, I caught the Firefly reference thanks to the power of TV Tropes. Well done, ma'am.) Sheesh. If she keeps getting overpowered and stupid at this rate, I fear for your/Rina's/Zeb's sanity in the later books. Do you want some backup? Ami knows Harry Potter, she can help you out...if you'd like her to, of course...

Also, what are "greengrocer's apostrophes"? Is that a special term for apostrophes ending up in the wrong place?

Anyway, minor concrit time!
"'Bip! Mr. and Mrs. Weasley. Human canons, 30% OOC and rising,' Rina said."
Funny, but what happened to their CADs? Did they all explode already or do they not work right in Potterverse because magic? (Zeb's imitation was less funny, tbh)

"The Sues ran at the barrier, and of course crashed into it."
Shouldn't that be "The Sue and Replacement"?

"'Oh, fine,' Rina sighed, and snapped the replacement's neck."
Not that I object to paralyzing Sues from the neck down and ensuring their death, but...it takes a fair amount of pressure to snap someone's neck. Should I assume that Rina used the rocks to help her and let the matter drop?

That's all I can find for now. Seriously, good frickin' luck with the later volumes. *hug of sympathy*

Doby stood to introduce himself

Also, “Well, looks like we have ourself our first charge!” looks weird to me. Rina may speak like this, but "ourselves" would be more grammatical, and honestly, I would just drop the word entirely.

And then there is this:
Neville insisted that they were only supposed to take two electives despite Hermione being able to take three in her fourth year without any problems.
Do you intend to imply that poor Neville is already so stuyfied that he, like Rose, should have read the books? It might be better to refer to something Neville could actually know, like Bill and Percy Weasley taking five electives in previous years, and actually getting all the O.W.L.s.

Despite this, I really enjoyed the ride.

HG

And I agree with you Mrs. Weasley would make Chuck Norris eat his vegetables, also she will ground Bruce Lee for week and make Batman agree to make friends.

In small ntipocky thing, you wrote "Chrismastime" in the last paragraph of page 29.

I'm enjoying these missions.
I like that the agents get to enjoy the canon setting such as when they have breakfast or when they slide down to the Chamber like it was a playground slide. The part where Zeb imitates Malfoy was funny.

BTW, you typed up, "Crabbe!Ron". I think that's supposed to be Crabbe!Neville.

And mad. And also brave, and also also mad. =]

I really enjoyed this mission, and it's worth mentioning that the balance of a Western longsword compared to a katana is really quite different. Also, I loved the DW references! I mean, I sort of would, but y'know. It's nice that they're there. =]

I've loathed Rose Potter for a long time now, good to see her getting her just deserts.

I did notice one typo in the mission, though.

"Rose summoned a mass of writing vines"

I believe that should be "writhing"?

Glad to finally see this finished! Congratulations on finishing another chapter of the saga, and can't wait to see the next!

And so Rose dies... again. Keep it up!
Minor nitpick... remember what happens when a phoenix dies? They burst into flame and are reborn. Presumably even Replacement!Fawkes is still a canon phoenix.
Not that it makes much difference; once the Sue is dead, canon should snap back pretty quickly.
(I feel bad criticising when you're being brave enough to take down a Legendary, but still... that's the curse of perfectionism.)