Why did you cut it into a head?

Because Cheng had an intersection with other girls, he cut off Cheng's head.

At the end of School Day, on Christmas Day, Cheng Ge abandoned and got back together. At this time, the woman who claimed to be pregnant came to Cheng Ge's house. Looking at the scum in front of him, he took out a knife and stabbed Cheng Dage directly.

Later, Cheng Ge's head was cut off by Katsura Kotonoha and Saionji Sekai was killed by Katsura Kotonoha. Finally, Ye Yan held her head in the boat and cried, but it was not her head, but Cheng Ge's head.

The root cause of cheng's murder.

Such an ending, the three protagonists have no good end. The world and Cheng Ge were killed and became murderers, which can be said to be a veritable field.

It was Yi Tengcheng himself who caused this consequence. Without his hesitation, Saionji Sekai and Katsura Kotonoha would not be discredited and he would not die. He can only say that everything is karma, but it's a pity that Saionji Sekai and Katsura Kotonoha are two girls.