Sestro /ˈsɛstɹoʊ/

Over the course of a month and a half in the beginning of 2023, the system introjected seven new headmates during a period of intense trauma processing and instability. As it started to stabilize, it was left with many lingering concerns, like Terezi being susceptible to the paranoid delusions and exotraumatic flashbacks that other members of the system sometimes experienced. The system was left without a manager that could withstand the brunt of what its brain could inflict on it.

Sestro and Hamifi arrived together, not unlike Dave and Rose, and immediately got to work together. They began sharing the position of system manager, allowing Terezi to heal and be able to front without the weight of systemwide responsibility. Being one of the system managers doesn't make him immune to being overwhelmed, however. When he burns out, he goes nigh-catatonic for a period, like in source. It only takes a few days to recuperate, and Hamifi handles any matters that may arise during those periods.

Sestro, an alphy fragment, inherits many of the traits other alphy fragments do: a bias towards indecision, getting stuck in his own head, and being unsure of his own gut feelings. Hamifi, a Charra fragment, helps him manage these traits. As an alphy fragment, Sestro is also more outwardly emotional than Hamifi, prone to moments of melancholy over specific people from his source.