Because we all wanna get more of him everyday!
The following are some characters of Harry Potter series including the way you might be able to use there names for your friends:
1. Umbridge:

Example:
“That professor again gave me a detention…”
“She’s just so Umbridge!”
2. Lockhart:

Example:
“Hey, heard the latest news, they say Eminem went into coma and ended up dead!”
“Why you talking Lockhart-ly ?”
3. Lavender:

Example:
“That shop keeper made you stand waiting for an hour?!”
“Yeah! He’s such a Lavender!”
4. Moaning Myrtle:

Example:
“I just can’t tell you how hard its getting day by day, i have to clean the floors, wash the cloths, go to school, do the homework, cook the food, I mean, its really getting over me…”
“Your life is crazy Myrtle, go on, moan a bit more.”
5. Pettigrew:

Example:
“She was with me for the last six years, and then she stabbed me in the back and went away with that other guy…!”
“Oh… that is a real Pettigrew move, that is.”
6. Molly:

Example:
“I just ran a bit further ahead of the group of them and she went completely Molly on me for that!”
7. Ron:

Example:
“Hey, I am so worried about the results, what do you reckon it’d be?”
“Don’t, worry, you’ll get an A+, you always do, you never get even an A!”
“Yeah, go on Ron, a bit more!”
8. Neville:
Example:
“Hey buddy, what do you want for your birthday?”
“My birthday was two weeks ago!”
“Shit!”
“Totally Neville!”
9. Percy:

Example:
“So yesterday, this poor old dear dropped her wallet, so I picked it up for her and…”
“Well, yesterday I helped an old dear cross the road, bought her a coffee, carried her bags onto the bus for her and gave her the last $10 in my pocket because she didn’t have enough for the fare.”
“Okay then Percy.”
10. Hermoine:

Example:
“You know, nearly 70% of our world is water only water!”
“Well, its 71.5 to be exact…”
“Yeah, whatever Hermoine!”
Collected And Prepared By Roxtar Amir
Source: Buzfeed.com