When someone you invite to a group or event, (usually a female) hijacks said group or event for their own purposes or desires.
"Wait, Faith doesn't want to go to Maude's Cafe? We decided on that weeks ago!"
"Yeah, so due to the Foster effect we're now going to the Westbrook Diner because that's what Faith wants."
"Yeah, so due to the Foster effect we're now going to the Westbrook Diner because that's what Faith wants."
by Hahayeah11 June 7, 2019
Get the Foster Effectmug.