Dear Imogen,
I noticed you finally read the past two cards I sent you this morning. I hope I didn't startle you, but I don't want you to know who I am until Valentines' Day.
"Being deeply loved by someone gives you strength, while loving someone deeply gives you courage." -Lao Tzu
My dearest love,
Your secret admirer.
P.S.: I heard you sing while I passed by your office on my way out to lunch today. You have a lovely voice.