Idolfap is a colloquial term used to describe the enthusiastic and often obsessive behavior exhibited by fans of K-Pop idols, particularly in online communities. Fans who engage in idolfap activities are driven by their love and admiration for their favorite idols, often expressing their passion through various forms of creative expression, from fan art and fiction to fan music and fanfics.
If we treat iu as a meaning “above” or “beyond”, then idolfap could be a compound noun . The morpheme dol may denote “boundary” or “threshold”, while fap might convey “act” or “ritual”. A plausible gloss, therefore, is: iu idolfap