The Su family members all signed the contract one by one, even if they wanted to refuse they had no other choice. It was already too late for them to regret their actions and now that Su Wan who no longer cared about her reputation was willing to break the pot completely, it was clear who was worried about the breaking of the pot more than her.
They all wanted to resist but when Su Yu Cheng tried to refuse he was beaten up by Su Wan until even his mother could not recognize him. After the heavy beating that Su Yu Cheng suffered no one in the Su family tried to say anything about Su Wan or the contract, they were worried that they will be beaten black and blue by Su Wan which was why they all turned a blind eye to Su Yu Cheng's beatings and agreed to go and see Lin Ze in the night.