Gary is very depressed as his one time fling with Anna quickly develops into some sort of psuedo marriage. Here's a shot of Anna coming to Gary's work, bringing him lunch.
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Poor lovable Dennis shows up at Gary's with a six pack of beers and is shocked to find his little sister, Anna, locking lips with his best friend Gary.
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Sure Gary tries to resist Dennis' little sister, Anna, kissing him, but when a hot, younger girl shows up at your house in a little skirt, what choice does a man have?
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Poor Dennis is just so excited to have Gary dating his sister and just wants his sister to date a good guy and to have Gary in the family.
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Dennis' sister, Anna, gives Gary a huge hug and he doesn't seem to be hugging back. Anna is definitely what we'd call a stage five clinger.
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Gary Unmarried Season 1 Episode 14 Quotes

Jack: Woh, deja vu
Gary: It's not deja vu, it's the fifth time you walked into the room!

Allison, I have the answer to all your problems, except your stretch marks and screechy voice...damn, we must have gotten disconnected.

Gary [on the phone]