wallflowering
the planned activity of attending a party or social gathering and blending into the background; wallflowering is a benign activity for shy people or individuals who enjoy listening in on conversations and engaging in harmless people watching; it is NOT stalking
Jason wasn't in much of a talkative mood so he was going to hit his buddy's party, do some wallflowering for about an hour, and then slip away quietly.
wallflowering by Sexy Simian December 4, 2010