Gaston has neat black hair tied in a ponytail and a gentle, though worn, face.
Three years after Guts' join date, Gaston is one of the Raiders who is shown to have a deep respect for Guts, both as a commanding officer and friend.
Gaston never regretted joining the Hawks but, as Guts revealed in a discussion with Casca, wanted to save up his earnings to open a clothing shop in Windham. He is unable to achieve this, likely because he was outlawed like the other members of the Hawks, but upon revealing this to his former commander, shows no sign of disappointment, instead joyful in the fact that his place was with the Hawks and that the Raiders were a family to him.
It is hard to say what the extent of Gaston's abilities may be, as he is never really seen in action. However, being ranked second in command of Guts' Raiders, it can be assumed that he is at least a fairly formidable warrior and strategist.