Fu (フュー Fyū) is a character that fully debuts in Dragon Ball Xenoverse 2. He is considered by Dabura himself as his rightful successor to his throne as King of the Demon Realm. Thanks to Towa he eventually became the new Dark King (暗黒王). He is one of the main antagonists of the Prison Planet Saga and the Universe Creation Saga.
According to Dragon Ball Online, Fu is unable to express himself or act on his own, as Mira exerts a substantial influence on him.
Fu is a bespectacled Makaioshin with a fearless smile. While mistakenly believed to be evil and an underling of his uncle, he prefers warping timelines to help others instead of causing meaningless destruction through his alterations, and is not interested in revenge or reviving the Demon Realm. Fu does not like to fight but instead loves science and the possibilities his changes in history can create, taking after his mother Towa but in a more positive sense. Fu's interest in science goes so far to experimenting on scenarios, the mechanics of fighting, and using time rifts and paradoxes for his own benefit such as creating time paradoxes on purpose in order absorb more power. However, once gaining some benefit from his experiments, Fu tends to try to use these benefits to better the world, making him neither truly good nor evil. As a result he can best be described as akin to a well meaning yet mad scientist of sorts who illegally alters history.
However despite his positive traits, he is still capable of engaging in questionable actions such as altering history illegally in direct defiance of Chronoa's authority and the Time Patrol's opposition, imprisoning various fighters from across time on the Prison Planet, and releasing the dangerous Core Area Warriors simply to make things interesting, and turning Cooler into his puppet by converting him into a Meta-Cooler. Additionally his quests also tends to meddle with the lives of innocent people of the timeline he creates or alters simply to satisfy his intellectual curiosity. He also became enraged at Xeno Goku and Xeno Vegeta for destroying his base and sought to punish them for their interference.