Using people's hearts as a chess piece and the world as a chessboard, who will win and who can know?
"I still remember when I first met you, you were not what you are now."
"I never regret what I did, I only regret giving you a chance to survive!"
"If possible, I really hope that we were born into ordinary families. That way we wouldn't be as full of suspicion as we are now."
Concept: They are supposed to be childhood sweethearts who can make fortunes and manipulate people.