KOTOKO (real name 堀川ことこ—Horikawa Kotoko), born on January 19, 1980 in Sapporo, Hokkaido Prefecture, Japan, is a female j-pop electronic/dance vocalist whose songs draws on electro rock, techno and trance. She has released five albums (three associated with Geneon and two associated with I've Sound), twelve maxi singles (seventeen overall) and two DVDs that were released in the US.

She also composes and writes lyrics (for herself as well as other singers in I've Sound) for numerous other song collections. She frequently works with the producers I've Sound, and has contributed songs to numerous anime and video games including Onegai Teacher, Mahou Shoujo Tai Arusu, Onegai Twins, Ren'ai CHU!, Maria-sama ga Miteru, Hayate the Combat Butler, Colorful Kiss, Kannazuki no Miko, Starship Operators, Shakugan no Shana, and BlazBlue: Calamity Trigger.

In 1999, she became a professional singer. Her first successful audition was with I've Sound, a team of producers using the talents of various female vocalists for their productions—best recognized for their many dating sim and eroge game soundtracks. Since then, she has performed opening and ending themes for a few anime and has gained significant recognition from her two I've Sound-related album releases. Her second album, Garasu no Kaze, released in June 2005 has been praised within multiple online communities. On October 13, 2005, she released her fourth maxi single, which featured a song from her Garasu no Kaze album, "421: A Will" and its B-side song called "Shuusou" (秋爽, The Refreshing Autumn Breeze), which is featured in her third album, Uzu-Maki.

Although not listed on her official Geneon website, KOTOKO has actually released four albums. Her very first album was called, Sora o Tobetara, which was released in 2000. Many of the tracks on this album were later re-recorded for her first I've Sound album, Hane (羽 -hane-, Feather), and was attributed as her first album. Her first I've Sound CD appearance was on the CD "Dear Feeling" (only released at "Comic Market 59".) with previous singer Aki. She then appeared on I've Girls Compilation Album Vol.3 "Disintegration", a series of albums with various songs from the I've Sound singers.

KOTOKO's first official performance in North America was her highly successful American concert debut at Anime Expo 2005, followed soon after by the KOTOKO Lax Tour. Now that her self-composed hybrid of pop and techno beats—sometimes pop—have crossed the Pacific, KOTOKO's lyrics have elevated her presence among thousands of North American J-pop/anime fans.

In 2009 she did the theme song for the Mamoru Oshii live-action movie Assault Girls. The song 蒼-iconoclast has also been featured as the opening theme song to the console version of the widely popular game Blazblue:Calamity Trigger. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Personality: Quiet, likes making new friends, optimist, caring, emotional, perfectionist, romantic.

Interests: Movies, shopping (online), photography, flowers, darts, softball, dancing, collecting cute things.

I want to go to: Switzerland, Netherlands, Sweden, Morocco, Greece, Egypt, Tuvalu, Bolivia, Nepal, New Zealand, India, Thailand, Australia.

Favorite food: Cherries, and particularly fond of strawberries, actually likes all fruit except melon, noodles, curry soup, avocado, cheese, milk, pudding, mint, cooked rice, chocolate, cookies, coffee.

Favorite things: Music, poetry, movies, the sky, the sea.

Favorite animals: Rabbits, turtles, sheeps, insects.

Dislikes: The dark, narrow spaces, a bad liar, rain, people without dreams.

Dreams: Go to Los Angeles, plant a lemon tree and build a house in the hills with a view on the sea.