Choco

Choco was an R2 unit with a rounded body and only one center leg who was a prisoner of the Great Heep on the planet Biitu. The clumsy droid was the first to encounter R2-D2 after he had been thrown, deactivated, into the Heep's Droid harem. Extending one of its hidden mechanical arms, the droid reactivated R2 and the two droids quickly became friends. However, the friendship suffered a setback after R2-D2 became infatuated with an egg shaped astromech droid named KT-10 and began ignoring the spherical droid. Following the defeat of the Great Heep, the spherical droid joined forces with the other liberated astromechs to revive KT-10, who had been completely drained of power as a result of being fed to the Great Heep.

Text and facts from the “Choco” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.