Don't fall victim to vampires! Don't get slashed by a psycho! Don't get stuck, ASK DR. ELDRITCH!
Dear Dr. Eldritch,
My friend, Halle, has a book of spells that she inherited from her aunt, and like she told some of us about it, and we tried some of the spells, like making Chelsea look like an old woman so she could buy us peach schnapps, and making the teachers' lounge smell like fish, and the other girls wanted to try some of the harder spells, like summoning magical creatures and cursing our enemies, but Halle and I said no, we shouldn't, but Kaitlain got in trouble from her social studies teacher for using her cell phone in class, so she looked up this spell for revenge and summoned this Horrible Thing, and I think it ate Mr. Elston, but it didn't just disappear afterwards, it's like eating the neighbor's pets, too, and attacking people and everyone is really upset and there's this curfew now until it gets caught but nobody knows what to do or where it came from, except us, and Kaitlain made us promise not to tell anybody, but I thought it would be okay to tell you because you wouldn't get us in trouble, so can you tell us what to do, and really quickly, because they're going to cancel the Prom if the Thing isn't gone by then?
-- Avril from Irvine
Oh no, the prom is at risk! Here's a tip; when soliciting help, at least pretend that your concern for others is greater than your concern for yourself. Luckily for you, narcissism isn't a disqualifying trait, so I'll give you some advice, but you'll have to sit through a lecture. A small price to pay, since you may learn something, but I won't even bet the traditional box of doughnuts on it. Now to get pedantic, and don't think you can skip it, because I'll know:
You are right, I won't "get you in trouble," because you've already done that. Perhaps what you are trying to express is a desire to correct the problem without bringing your role in this fiasco to the attention of the authorities. This may be possible.
The good news is that such summonings are usually terminated if the summoned creature kills its summoner. If you're willing to sacrifice Kaitlain, this is an easy solution. I'm certainly not advocating this, but consider that Kaitlain is a loose cannon who's tasted unearthly power, so you know she'll be back to the well like a sweet-toothed parent the day after Halloween, and it will only get worse.
Okay, now listen up: Self-taught magic is a bad, bad, bad idea. What if you summon something with an unnatural interest in eating your spleen; would you know how to stop it? Learning how to close a multi-dimensional vortex after you've opened one gives you incentive, but odds are you'll be sucked into "somewhere else" before you finish the lesson. About seven percent of disappearances in the world are due to such dabbling. Even if you stick to love potions and scrying spells, you aren't trained to deal with things when they do go wrong, and they WILL GO WRONG! Self-taught magic is like learning to fix toasters by plugging one in and poking around the inside with a screwdriver. The lesson you learn my be woefully different from the one you wanted.
The Dark Arts (called that because they're part of the Shadow Realm) are best learned through apprenticeship. The one-on-one relationship allows the Master to carefully monitor and guide the student's training. Most of the first phase deals with protection; how to shut the valves, close the doors, contain the ichor, and not get eaten. Then one learns control; how to make the pixies dance. Only when all that is mastered does the student learn how to open the doors, turn on the lights, and invite the supernatural beasties in. Even with Master tutelage, apprentices sometimes disappear in a puff of smoke, or conjure a gibbering demon that eviscerates them before it can be contained. Studying wizardry is more dangerous than handing out ACLU bumper stickers to Compassionate Conservatives.
Unfortunately, certain works of fiction depict magic being taught at boarding schools, as if it was as simple as the social studies class taught by your ex-teacher. The thought of a classroom of prepubescent wizards-in-training gives me the willies. One might better teach children how to make dynamite while blindfolded.
I hope by now you see that Kaitlain's invitation to the Horrible Thing is like turning on the ecotoplasmic fire-hose while holding it loosely with one hand, and not having a wrench to shut it off. Assuming you still want to keep Kaitlain around, you'll have to destroy the Thing yourselves. Look in the book for a "Spell of Negation" (that means, like, totally bagging its face (you Young People still say that, right?)). Read it CAREFULLY, so you understand exactly what to do and what equipment you need. You'll have to lure it to you and cast the spell after it's in range and before it does something Horrible. Make Kaitlain stand in front, just in case. If you do it right, you'll send the Horrible Thing back from whence it came, and you'll live to see the Prom.
Good luck, and if I don't hear from you, I'll know how it came out!