The culprit.

"Why?" Lin Xiyan didn't understand. She tried hard to control herself from crying, and then looked at Grandpa with tears in her eyes.

Grandpa could always calm her down, but the next words made her unable to calm down. Grandpa said, "Because... I thought Cheng Jiujiu liked men, so before you met me, I used a time machine to change Cheng Jiujiu's genes to female. He... can't see Cheng Jiujiu anymore."

"So, my brother is actually my sister?" Lin Xiyan was shocked, and grandpa sighed slowly. The time machine is not foolproof, and changing time and history may cause faults. "Yes, because of the secondary impact caused by my teleporter, I am not sure whether it is a man or a woman when I meet Cheng Qijiu again. I don’t know whether the Cheng Qijiu I meet will be the Cheng Qijiu who wants to kill you for a man, or you who is willing to protect world peace for you. This is why I don’t want you to use it."

"So, I will never see my brother again. I can never call her in front of him again. Cheng Qijiu, whether you are a brother or a sister, I like you very much. You are my only relative."

Lin Xiyan recognized the last Cheng Qijiu. Lin Xiyan didn't want to see the man who killed her in her previous life. And if the person she met in her next life was a new Cheng Jiujiu, she wouldn't mind.

There was only one brother, Cheng Jiujiu, who treated her like a sister.