[Sister and brother + yandere + sweetness + slight coercion + male protagonist fighting and fighting + mutual redemption + wealthy family]
When they first met, they both went through the most painful quagmire in life, licking each other's scars and coming out of it, but they got separated by accident.
When they see each other again, she treats him as a simple "little puppy", acting coquettishly with soft eyes and approaching him with clumsy gestures. Gradually falling into the trap of tenderness - his carefully designed interactions; those caring companionships, hidden step-by-step calculations; even the occasional "vulnerability" is a bargaining chip to control the sincerity.
When she was shocked to realize that the "little milk dog" was actually a "beast" that moved at the right moment, her emotions had already become entangled like vines and she could not break free.
