Two's company (, three's a crowd) spoken language informal
When two individuals desire to be alone with each other, a third person is not welcome.
A: "Lisa wants to go shopping with her boyfriend. I think you shouldn't come with them." - B: "Two's company, three's a crowd."
Used to tell someone to keep secret what you're about to say
The room you are currently in.
Kept in secret
To secretly punish or rebuke someone for doing something.
A place or condition in which there is no privacy.
In the late 1500s, this idiom appeared and initially referred to lovers who wished to be alone.