Went to M&S today and bought some Girls' size (15-16 yrs) 底底. I'm surprised they fit even a little big. I'm 30" waist and these 底底 look as though they fit 31" perfectly and might even work for 32". They must be designed for westerners so the sizes run big. The design is conservative, but is a classic style for girls really...
You can go to M&S website and check the style, under School Uniform and Girl's Underw. They are available in-store in HK so don't have to buy from UK and pay shipping. Plus shopping in the kids clothing section would make you feel less embarrassing for sure

Hope you find this useful.
覺得好的就按一下感謝吧~~

香港咁多選擇、點解要去馬沙買、街邊Ｄ款都靚過佢

It's true that HK has sooo many more choices

怕尷尬就試下去馬沙囉
啲職員好專業架
唔會笑你或者拒絕做你生意

just walk in and try on their shoes, look at their hosiery and underwear...

貴好多，比起街邊啲鋪... but enjoy la
Alena also good haha, little bit cheaper. $20-25 underwear