You know who.

Good evening, I’m kawa.
Last weekend, I watched Harry Potter movie.
What? You think I’m weird because Harry Potter is a movie for child?
Ok,ok. I got it.
But men have boy’s minds forever. Please leave me alone.
Anyway, I watched the movie and I found a interesting phrase.
The phrase is “You know who”.
In the movie, the phrase is used to say the name of the worst evil wizard.
I guess we can use various situations.
I may be wrong, but I will make a short story.

[1st story]
A:I saw a famous singer yesterday.
B:Who?
C:He is a tall, long hair and has beard, Mmm, well, you know who!.
[2nd story]
A:Hey, Have you heard? Our boss is having an affair.
B:Really? Please tell me in detail.
A:I saw him and a young woman to make out in front of that station.
B:A young woman? who?
A:she is a our colleague. short hair, big ears, wear glasses, about 25, you know who.
B:I got it. you know how. Wow! She IS. Unbelievable!
I guess this phrase is fit in housewive’s gossip.
Why don’t you use this phrase which is “You know who.” ?
See you.