Tomas was a well-built man of average height. He had shaggy dark hair with a thin goatee and mustache. He was commonly seen wearing the uniform of the Scout Regiment with a green v-neck underneath.
Tomas was a trusted soldier, as he stood alongside other superiors such as Miche Zacharius and Nanaba. He was shown to be very strong, both physically and mentally as he pushed himself to travel on horseback for several hours in order to get the news of Wall Rose's breach to Commander Erwin as fast as possible.
Tomas is among the soldiers brought by Miche Zacharius to monitor members of the 104th Cadet Corps who are suspected to be accomplices of Annie Leonhart. As they discuss the possibility of an ally to Annie being among the cadets, Miche smells several Titans coming from the south side of Wall Rose and he quickly tells Tomas to alert the commanders.
When Hange decides to oppose Eren's plan to destroy the world beyond the Walls, Tomas is one of the soldiers remembered while Hange tries to convince Jean and Mikasa that their fallen comrades would not support destroying the world.