Sexy Grandad Legs

When someone has kinda good legs but not really

Jessica: how do I look?
Tumblrina: you have sexy grandad legs.
Jessica: what?
Tumblrina:I said you have sexy grandad legs you idiot.
Jessica: what does that mean?
Tumblrina: ssssssssssssshhhhhh
Jessica: o..ok

By Elinore

Define Sexy Grandad Legs Meaning