The staff at JJ Spa (Foulk & Silverside) is all Korean.
Foulk Healing (corner of Foulk & Naamans) also Korean.
Ruby Spa (Kirkwood Hwy near Elsmere) is a Korean shop.
If you want to travel further, Rainbow 7 in Newark and Royal Spa in Bear are Korean R&T shops, and give professional-grade massage.
The ladies at all of these places are always happy to converse in Korean.
I don't think there is any Japanese talent in DE, at least not that I know of.