Calling him Sir is acceptable in nearly any setting. Except perhaps with family.

Punishment in public. One single swat to the ass when around strangers would not raise any eyebrows. However if he wants to hit home that your being bad, his arm around you, and his hand on the back of your neck. tug lightly no the short hairs on your neck. Make you whence some. Would be acceptable as well.

Enjoy

V/R
ID