I’m surprised that some of my friend’s doesn’t know about this joke.
As described in URBAN DICTIONARY, It’s… Hell! I’ll just quote what I find the most appropriate explaination for such joke:
1. Used to add sexual innuendo to a conversation.
2. When a male wants to share with his friends that he was with a girl (whether her was or not), he will respond to a phrase that sets up “that’s what she said…” as funny or sexual.
3. To imply that what is being talked about was actually a sexual statement and that a girl agreed to said statement in the recent past.
4. Something people say after a phrase is said by someone else to add emphasis.
5. A phrase said by one male to another after a story about her was told to imply that he was with the first male’s girl after him.guy 1: wow, that’s a really big spear!
guy 2: that’s what she said!guy 1: man, my girl was hot last night!
guy 2: that’s what she said!
Well, I’ll just leave the URBAN DICTIONARY definition to it… I wonder how can we change it to a Kuwaiti version 
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