Tup, whose clone trooper designation was CT-5385, was a clone trooper who served in the 501st Legion of the Grand Army of the Republic during the Clone Wars. Tup was considered a rookie when he began his service under Clone Captain Rex at the Battle of Umbara. He grew close with fellow soldier ARC trooper Fives during the campaign. When the clones were eventually betrayed by their temporary commander Jedi General Pong Krell, Tup was instrumental in the capture of the rogue Jedi.

The 501st Legion, also known as Vader's Fist, was an elite unit of clone troopers in the Grand Army of the Republic during the Clone Wars. They were known for their blue markings and their close association with Jedi General Anakin Skywalker and Commander Ahsoka Tano. The 501st played a significant role in many battles and were instrumental in the execution of Order 66, turning on the Jedi. They later became a prominent stormtrooper unit in the Imperial era.