I've bought some clothes for my girl at Hushush (a japanese dept store similar to Comme Ca) at Shatin (the plaza above KCR station) .
For any purchase of a pair of pants or a skirt/dress, all items can enjoy 30% off. And purchase of $200 (after discount) will enitlte a short-sleeve t-shirt ( which you can choose among a few style & colour).
I've bought 2 pants & 5 t-shirts for my daughter. The bill is about $710 & I brought home 10 clothes (as 3 free t-shirts for every $200 purchase).
I think these japanese style wear are comfortable & suitable as casual wear.
I seldom bought Japanese style stuff for my kid as I think it's "too cute" sometimes & too much details. But stuff of Hushush is not too cute as compared to many other Japanese brands.