Kang Sae-byeok is very stoic and usually barely expresses emotions. She is determined during the Squid Game and kept to herself in the first three games. She is also level-headed and can stay calm in dire situations. When Ji-yeong sacrificed herself so Sae-byeok could advance, Sae-byeok is shown crying. She Sae-byeok is very quiet and calm, never panicking even in stressful situations.  warmed up to Gi-hun and later trusted him for his promise to take care of her little brother before she died.