Miku

Miku (ミク) is a key figure featured in Sages of Time.

In the original timeline, Miku was a Skywardian who gained notoriety for being able to tell future events, and her ability to travel through time with the help of the Time Watch, but its effects caused her to age. Because of this she sought out an apprentice and successor to pass down her abilities.

Alistair Black became her student, but his increasingly violent nature forced her to strip away his powers, but was sealed away by him. Several years later, Reid and Azure freed Miku; as a token of appreciation, she helped send Travis Asher back to the past.

New Timeline
Like Reid, Azure, and the other Skywardians, Miku does not appear to exist in the new, altered timeline caused by Travis' actions upon returning to the past, likely due to that very reason. When Travis regains his memories from his previous incarnations several centuries later, he asks the Oracle about the Skywardians from the original timeline, to which she responds that they live on in a world separate from theirs.