chaos (ケイオス keiosu) from Xenosaga joined the Elsa Crew two years prior to the events of Episode I.
Photo by Yenra
He is described in the official design materials as the one who ensures the safety of the crew during their travels. In that respect, it could be said that chaos is ship security, as he certainly serves that function. But he also serves in many other ship tasks, such as several in-flight functions and the moving of cargo. Essentially, he is a jack-of-all-trades.
Japanese Voice Actor: Hoshi Soichiro
English Voice Actor: Derek Stephen Prince (Xenosaga I), Joshua Seth (Xenosaga II & III), Clint Bickham (anime