A Capable Sister

"Yes, it is forbidden for humans to use. But Angels can use it. Because it is not a life energy as humans think. It is greed or desire energy. The people who wish to use zu energy need to be greedy. The greedier you are the more zu energy you have."

"It gives you endless powers with endless desires. It is cursed for humans. That's why it is forbidden for them. But angels have no wishes. They don't seek anything. They can see and absorb zu energy without any side effect.", Juli told her.

"But I had heard. That with zu energy you can predict the future, grow the crops, control the weather and many other things.", Princess Diana asked.

"Yes, you can do all these things. But in the start, this energy was only bestowed on the royals or the selfless humans. Soon, everyone desired to use it and ended up with the unescapable desires of human nature. Soon, there was destruction and this energy and the teaching of it got forbidden.", Juli explained to her.