Amnesia is a story by Yasmin3140 and here is the description

Almost after 2 years of dating JUngkook and Taehyung are happily living in south korea with taehyung debuting his first album in a week and Jungkook being part of one of the most succesfull k-pop groups with his two older brothers. Everything seems to be going great until tragety strikes when taehyung is believed to have died during surgery following a car accident. In attempt to help deppressed Jungkook move on following his boyfriends death his 2 brothers and a couple of friends on a getaway trip which leads them to uncovering the truth behind what happend that faithful night 

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