Some encouraged me to start writing for I can brush up my writing.

Here's the problem, I don't know what to write -_-

I want to write about ririn for it's hard for me to find good, readable ririn fanfic.

Could you help me? 

Give me some suggestions what story/topic I should write? What theme I should choose etc

Seriously, I need to brush up my writing skills, grammar, words used in essays (in this case, the story) and whatever you think that's necessary.

Thanks in advance & I really hope you guys could help me *sigh*