Blood Donor

Like clockwork, Harold went to the blood bank every sixty days.
At first, he kept a calendar. Big red circles, dutifully crossed off each time.
He’d been doing this for twenty years when one day the receptionist held up her hand.
“There’s a note on your file,” said the receptionist. “One moment please.”
Harold wondered what it was about…
Was it some kind of disease they found?
What is a horrible, incurable disease he’d gotten somehow?
Was it… was it…
The receptionist put a cap on Harold’s head.
“Happy twentieth anniversary!” everybody shouted.
Harold thanked them when he came to.