“Compersion is said to be a non-sexual state of empathetic happiness and joy experienced when an individual’s romantic partner experiences happiness and joy through an outside source, including, but not limited to, another romantic interest. The concept is now widespread within the polyamorous community.”
A few words to follow up on this idea…
Compersion is almost like the total opposite to jealousy.
When you experience compersion, you experience the joy and pleasure that your partner has when they are with someone else.
This idea is similar to the concepts of limbic or emotional resonance which are our natural potential to experience someone else’s emotion just by being in their presence.