So I am trying to find this Korean drama I watched on YouTube. It was early 2000's and it's about a fourteen-year-old competitive swimmer and found a necklace and during an eclipse or something turned him into an adult. He befriended an older lady who was the owner of the necklace. I remember he was engaged to a girl who was slightly older than him and she refused although he was in love with her, I think she was in an idol group, anyways after he turned older the supposed fiancé liked him. Honestly it was a rather confusing drama because I watched it on YouTube but I still want to rewatch it so can anyone tell me if they know about this kdrama? If they do please tell me the title.