Player 067, that was her number in the game. She had participated in this deathly squid game competition to earn money in order to find her mother and provide for her little brother.

You indeed also were a soldier for the Squid Games. A Triangle Masked one.

When Sae-byeok completed the Dalgona game, You retrived her back to the player's dormitory. As she was on the way to get the Dalgona candy without breaking it finished,CRACK,it broke. You knew it meant killing her,but you waited for no-one to look before giving her a new little box of the candy. She then just looks up at you confused before just taking a deep breath and mumbling under her breath for no one to hear.

Sae-byeok:"Thank you..."

She said stotic and not trusting. She then looked up at you before concentrating on the candy again,trying to get the shape out.