I made this joke story up myself, I didn't take it from the internet. Enjoy! (Note: McGonagall's is not an actual restaurant in the Harry Potter series, it's just a play on the name of McDonalds!)

Me: I'm going to McGonagalls!

Boring person who dosen't like Harry Potter and dosen't know anything about the series (but does know it is unhealthy to eat too much junk food): Typical teenager, eating junk food and drinking coke at McDonalds.

Me: No I'm going to McGonagalls! Didn't you hear me right?

Boring person:What-

Me: And excuse me, I don't drink coke! I'd much rather drink Butterbeer!

Boring person: -are you talking about? Who is McGonagall? 

Me: Professor McGonagall is the head of Gryffindor house!! (despite not being in Gryffindor myself)

Boring person: ............. (speechless)

Me: You don't what Gryffindor or Butterbeer is, or even who McGonagall is? Watch out, Beaky's gonna hunt you down!

Boring person: You lunatic!!

Me: How dare you insult Luna Lovegood?!!

(Ginny turns up by Apparating)

Ginny: I agree! Don't  say that to her, Luna is way more awesome than you! (blasts him with the Expelliarmus jinx)

Boring person: ........... (speechless again)

(Buckbeak flies in and starts attacking this random person who insulted Luna)

Boring person: Aaaaaaaaaaaaaaaaahhhhh!!!

Me and Ginny: Hehe....