When it comes to consent, what's usually discussed is getting consent from the person with whom you would like to have a physical interaction.
What's not talked about as much is giving consent to your partner on what you're comfortable with them doing with others so that they don't cross any boundaries you may have.
The tricky part to this whole thing is doing it without being too controlling or possessive. After all, shouldn't each person have the right to their own body and actions? (You're not the boss of me!)
Let the discussion begin!