He remembered, when he was a child, being taken out of an underground grave by his masked grandfather, he seemed to have seen this type of Evil Ghost.
He doesn't remember how he appeared in that huge tomb, nor does he know why he recognized the Evil Ghost.
But he remembers, after returning that day, his grandfather never woke up again.
At that time he didn't know why, but now he knows.
Suddenly, he remembered, when he was two or three years old, his grandfather held him in his arms, told him stories, taught him rules, many things he couldn't possibly remember back then.
One rule was that once you put on a mask, you cannot be called by your identity.
And back then, in the graveyard, he called out to his grandfather.
Because he had seen his grandfather wearing a mask more than once, he could recognize him at a glance.
He doesn't remember what happened next, only that the next day, his grandfather never woke up again.
