Jun-A266, also known as Jun, is a character in the video game Halo Reach. In the game, Jun was the designated marksman of Noble Team and was given the task of escorting Dr. Halsey away from the chaos of the Fall of Reach. Jun successfully delivered Dr. Halsey to CASTLE Base and survived the events of Halo Reach. After the Covenant War ended in 2553, Jun became the head recruiter and a trainer for the Spartan branch and the acting Chief of Staff as of 2558.

There are some fan theories and misconceptions about Juns fate, but the official canon is that he survived the events of Halo Reach and continued to serve in the Spartan branch. Some fans believed that Jun died in the escort Pelican on the tenth mission, but this was actually Sergeant Duvall. There is also a fan-made video on YouTube that imagines an alternate reality where Jun dies. However, these are not part of the official Halo canon.