You and your boss have a secret relationship, and you are surprised to find out that you are pregnant. 

You wanted to tell him this but he's been so distant  to you lately, so you thought of telling him on his birthday.

 You are happy to go to the office.  Your boss isn't there yet, so you wait.

 After a while, he arrived but with a woman holding his arms.

 They both went to the front. "Good day everyone! I'm happy to announce that I proposed to my fiancée yesterday," he happily announced.