Exactly why Charlene Choi Cheuk-yin and Gillian Chung Yan-tung of Twins are so called is a bit of a mystery as the duo don't share the same genetic makeup.
Real-life twins Jill and Janice Vidal (better known by their Chinese pseudonyms Wai Sze and Wai Lan), however, are carbon copies of each other. They sing too.
'I'd consider myself more outgoing,' says Jill, whose music is self-described as 'faster, and more upbeat' as opposed to her sister's more R and B love ballads.
Though the 23-year-old Filipino-Korean sisters are on their way to success, Jill admits that if the Twins weren't around, she and Janice would have scooped up the opportunity to market themselves together.
'They're not twins and we are ... and the way they sing is different,' says Jill.
Both perform in English and Chinese, even though their conversational Cantonese is still basic. While Janice already released two albums and swept all the best newcomer awards in January, Jill also got her debut Hit Me released last month - and she's hoping that young girls don't get offended by her music video for Get Out.