
Play gooseberry
Unwanted Presence
The phrase implies the person's presence is intrusive or uncomfortable for others, especially a couple. 
Romantic Context
Often used when a couple wants to be alone, and a third person is present, making the situation awkward. 
Idiomatic Usage
Understand it as an idiom, not to be taken literally. 'Gooseberry' doesn't refer to the fruit in this context. 