Tomono was born in Japan where she studied music at the Yamaha Academy under Fumiko Eguch. Whilst in Japan, Tomono won a number of competitions including the first prize at the PTC Piano Competition.
Tomono went on to play at the gala concerts in major halls of Tokyo such as the Casals Hall and Orchard Hall. Tomono has also been composing since the age of seven and has written over ten pieces including a piano concerto.
She has performed her compositions, all over Japan, and joined the prestigious concert tour to Israel. Her performances of those pieces were broadcast on television and recorded by Yamaha. In 2000, Tomono was awarded a scholarship by the Yamaha Music Foundation and invited as a scholar to study with Christopher Elton at the Royal Academy of Music in London, where she has been given scholarships and won several prizes, including the Douglas Cameron Prize, Greta G. M. Parkinson Prize, Leslie England Award, Andrew Sykes Award and Kenneth Sidney Brindle Award.
In recent years Tomono has appeared both as a soloist and chamber music player throughout the Netherlands, Japan, Italy, Spain, Egypt and England, in venues including the Snape Maltings, Aldeburgh, and the Wigmore Hall, London.