Ches'sarro Seeto was a Bajoran collaborator during the Cardassian Occupation of Bajor. His name was the first to appear on a list of collaborators held by Vaatrik hidden in his chemist's shop aboard Terok Nor.
In 2370, during Rom's attempted recollection of the list, he recalled his name as Ches'so, from which Kira was later able to determine as Ches'sarro. He was found drowned in his pond on his property. When Odo learned about the engineer's death from Kira, he requested from her that she advise the medical examiner that Odo wanted an autopsy on the body and his death be treated as a suspected homicide. Odo believed that he was murdered by Vaatrik Pallra after he questioned her about the identity of Ches'so. He suspected the motivation for the murder might be the elimination of a lead for investigators. (DS9: "Necessary Evil")