Hinouchi Emi was born in Osaka, Japan on September 7th, 1982. She and her family moved to Taiwan when she was only four. They lived there through out most of her childhood, moving back to Japan when she was fourteen. After she returned to Japan she started writing music and composing music. The first track she completed was named "Painful" (Which later went on to be her fourth single).
Hinouchi soon started performing with a local indie bands. When she was 16 she entered an audition held by Takahashi Taku of m-flo and performed "Painful". She was then signed to Taku's record label Tachytelic Records. She debuted in 2002 as 日之内絵美 and released the single "Magic / World", which was produced by Taku. In 2003 she went on to release three additional singles, and in Novemeber came the release of her debut album, "Dramatiques". All of her singles, with the exception of "Freak!", have ranked in the top 150 on the Oricon Charts.
Hinouchi soon began composing music for Heartsdales and singing back up for them. Her first appearance with them was on the "I See You" single. She continued to work with the group until their spilt in 2006. She has also done a lot of work with m-flo. She has been featured as one of the reacuring artists featured in the m-flo loves... series and is part of "m-flo's family". She has co-written loves... song such as "Luvotomy", "Simple & Lovely", and "Love Don't Cry".
There was a three year period in which Hinouchi wasn't making any solo releases. During this time where Hinouchi started her radio show Hinouchi Emi no Renai Kai Kei Club Love. The raido show ran on Nack5 from April 2007 to March 2008.
In 2007, Hinouchi released her fifth single, "O'kay", which signaled her comeback from a period of three years which no solo releases. Her new releases were credited to 日之内エミ. "O'kay" and "Goodie Memories", released after this hiatus period, charted higher than Hinouchi's previous singles. Hinouchi went on to release two more singles in 2008 ("Ai Dake Ga" and "Kataomoi"), followed by her second, "ME...". The album included collaborations with Ryohei, SOFFet, and MAKAI.
In 2009, Hinouchi was dropped by her record label, KING RECORDS. The label dropped her after her second album failed to sell enough copies.