LKS has Yuna at 5'. I thought she was shorter, I remember her as a tiny little gal. The 90 lb weight, and B cups seem right.
She used to be in an unusual 3 girl apt. with street entrance and 2nd floor up stairs.
About 5 years ago...
I saw Gigi a few times when Yuna and Kat were there. Once I showed up for Gigi, but Yuna answered the door. When I saw smaller Yuna, I was puzzled and not sure since I had only seen Gigi once, so I said "Gigi?". Yuna laughed, then Gigi came out from behind a blind, also laughing. So, I think they did it on purpose as a joke, like to see if an old white guy could tell the difference between half naked Korean girls.
I never saw Yuna, but was tempted. She had a great reputation for being energetic nympho, but was too skinny for my taste.