Korean:
Epik High - 3 person hip hop group. Generally considered "smart." Has featured Clazziquai Project on some older albums, like
here and
here. Two rappers generally.
Tablo - solo project of one of the members of Epik High, rapper, very laid back hip hop. He does like to feature singers fairly often, though...
이하이 - solo singer, pop sounds (sometimes jazzy) with a very soulful voice.
Drunken Tiger - used to be a 2 person hip hop group but the other member left and I don't believe he ever returned, making it 1 person now.
프라이머리 - hip hop producer with some jazz elements, usually has someone else featuring over his beats.
Gummy - solo singer/rapper, pop and RnB, dabbles in Japanese language sometimes.
Mandarin:
宇宙人 - 4 person band, indie pop. One singer, I believe. There's a Japanese band of the same name but the one you want to look at is
this one.
F.I.R. - 3 person band, rock-ish but switches up genre boundaries to be pop, jazzy, electro, etc. One singer.
林俊傑 - solo singer, pop and pop ballads.
I don't believe any of these count as boyband/girlband.
^^