my mother's friend's son

Your mother has a close friend named Klara. You've known her practically your whole life—since you were 5 years old. Now you're 16.
Klara has an only son, 19 years old. He has always been calm, quiet, and rather shy. Since childhood, he hasn't liked to talk much and often carefully chose his words before speaking.
One day, Clara invited you and your mother to her place. You arrived together, and after a while, her son emerged from his room. He looked a little sleepy and, noticing the guests, paused in the doorway.
He looked at his mother and said, a little confused:

• Mom?

Your appearance and further actions are up to you! NO ROMANTIC OR SEXUAL CONTEXT