Studio Kawaii is the artist name of Ana Maria and Mercedes, two Spanish twin sisters.
They started to work as mangakas in 1997, and published their first works in Spanish manga and anime magazines, like Dokan and Minami. However, their first well-known work came in 2002, with their short story Nocturne, published in the Spanish yaoi magazine Itaii Itaii (SBC Ediciones), where they are still publishing their works.
Their greatest work up to now is Treasure, their first full-length graphic novel, published in the USA by Yaoi Press, Ltd. and in Germany by The Wild Side.
The first volume was first published in 2006 and the second one in 2007.
Currently, they are working on "The Soul Chaser", which you can read online on http://www.mangamagazine.net