How old is the woman in white?

I know the woman in white is fifteen years old. Qi was brought back to the organization by the leader himself at the age of fifteen and became one of the Shadow Seven. We can know from Ah Qi's memory that in the first year after he joined the organization, he accidentally saved a woman in white, when he was 75 years old. Qi is the protagonist of the animated assassin Wu. The main line of the story is the protagonist Wu's search for lost memories, and the branch line composed of love and hate runs through the characters. By telling the interesting things that happened between the hero and different characters in the process of helping others and finding himself.