It means your vary tough
Nails for breakfast with no milk was something from hat show spongebob squarepants wher the main character spongebob tries to go to a place called the salty spittoon
Fish: Welcome to the salty spitoon how tough are you
Other fish: how tough am i?! How tough am i?! I had a bowl of nails for breakfast this morning!
Fish: yeah so?
Other fish: Without any milk.
Fish: right this way sorry to keep you waiting

Nails for breakfast without any milk
by The person who did your mom August 15, 2022
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