when you or someone else is a really big fan of someone or something, but you don't show it and/or you don't support object of interest that much
girl one---omg, Young Jinsu's comin to ATL! wanna come to the concert with me, u love Young Jinsu

girl two---no thanks. i've already downloaded all his myspace songs. why go to the concert?

girl one---u are the biggest ghost fan i know
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