Brint Takashi is a member of the Hystorians and is one of the two people (the other being Mari Rivera) who told Dak Smyth and Sera Froste about the Hystorians and the SQ. Not much is known about his history except that he attended Amancio High School (in the original timeline) or Columbus High School (when the 1492 Break was repaired).
Brint first appears in the Hystorian headquarters. He convinces Dak and Sera to work for the Hystorians and fix Great Breaks. When the SQ (led by Tida aka The Lady in Red) attack the Hystorians' stronghold, He is seen defending himself.
Later on near the end of the book, he is seen with Mari Rivera in the Hystorian refuge base.
Brint appears with Mari to express his "gratitude and admiration" for fixing eight of the Great Breaks. When Mari told Dak, Sera and Riq they need to come back to the present to get a new SQuare, which may cause paradoxes, he says that there is no other choice, and the hopes by the point Dak, Sera and Riq are at with fixing the breaks, history could cope with the said paradoxes.