Milkshake

[Seafood]

After ordering a milkshake, a man had to leave his seat in the restaurant to use the rest room.

Since he didn't want anyone to take his shake, he took a paper napkin, wrote on it, "The world's strongest weight lifter," and left it under his glass.

When he returned from making his call, the glass was empty.

Under it was a new napkin with a note that said "Thanks for the treat!" It was signed ......

"The world's fastest runner."