RMA backstory (My AU)

Liu

Liu is a really smart boy and a great inventor.
His mother was a nerd when she was little. His father is an inventor, he teachs liu how to create things including his big sister, shan.

At first, it was a really normal life but then... Something is wrong...
That day, His parents had a argue with no reason, every. Single. Day.
The arguement really scared liu but his big sister comforts liu when their parents had a argue.

When he was 14, it became worse... His mother want a divorce 'cause she has enough of arguing, after the divorce... She leaves the house. His father blames liu for making his mother leave then... He leaves too.

Liu was really depressed and he blames himself for making his parents leave but his happy that his big sister didn't leave him all alone.
When he was 15, a police came to their house, he reports that... His parents died because of an accident, shan and liu was really shocked to hear it.

After all of the past, liu is 16 now. Shan creates a robot name mr. Suitcase for liu, liu was really happy but that's not all... His big sister went missing because of a red explosion in his room. Liu was traumatized by it but he's not alone because he has his best friend, mr. Suitcase.

After shan went missing, liu decides to join the championship for his big sister because he thinks shan is dead for a reason.

(me: sorry if my grammar is wrong)