Prior to the Clone Wars' outbreak against the Separatist Alliance, Esu Rotsino was a female politician representing her homeworld, the agriworld of Abrion Major, as a senator in the Galactic Senate of the Galactic Republic. Following the commencement of the war, Rotsino spearheaded the secession of Abrion Major and the other worlds within the Abrion sector from the Republic to join the Confederacy, citing unfair trade practices and restrictive bureaucracy as the reasons.
After their defection, Rotsino continued her senatorial service, now representing the sector within the Separatist Senate. Furthermore, the Confederacy was able to leverage the Abrion sector's foodstuffs supply, thanks to the senator's secession, to persuade starving star systems to align with them.
The new Star Wars canon first referenced Esu Rotsino in Rise of the Separatists, a 2019 addition to the Star Wars Roleplaying series by Fantasy Flight Games. Within Star Wars Legends continuity, Esu Rotsino debuted in the HoloNet News article "HoloNet News Vol. 531 52," penned by Pablo Hidalgo and Paul Ens and released on April 18, 2002. The character's name is a tuckerization of Sue Rostoni, who was the executive editor at Lucas Licensing at that period.