Rika (Becoming a Vocaloid)

Rika is a girl who was turned into a Vocaloid once day by mysterious circumstances. Her name before turning into a computer program is unknown. Her age and appearance has undergone several changes over the years, but her canon age in the book Becoming a Vocaloid is 13.

In Becoming a Vocaloid
Rika wakes up on a Saturday morning to swoon over her neighbor Nathan, when she is transported to the world inside of a computer. She is then introduced to Hatsune Miku, who welcomes her and helps her through her transition to becoming a vocaloid. Afterwards she is introduced to the rest of the Crypton Vocaloids and finds a particular attachment to Kagamine Len.

From then on, she goes on misadventures with the Vocaloids and eventually starts a romantic relationship with Len at the end of the canon story.

UTAU
Rika has an unreleased Utau. Her Utau's canon age is 17 years old.