A label designated for one who does not make plans of their own, but leeches off of other peoples plans. Generally they are not welcomed in but seen as a pest when they show up unannounced.
Person #1: Janaye and I were going to spend some time together last night with Quincy and Emily, but then Tim showed up and our plans were ruined.

Person #2: Ew gross, Tim is such a Plans Parasite...
by Son Bon July 16, 2011
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