The two current demands of the Maoist are:
"Proclamation of a republic by the interim parliament and a fully proportional representation (PR) based electoral system for the CA polls" [form one of the eKantipure article, link]
Myquestion is:
What does "fully proportional representation (PR) based electoral system for the CA polls" mean?

Can someone please elaborate, maybe with some practical examples as to what this means. I am trying to understand PR based electoral system within a Republican framework. Also, why this PR system was not acceptable to SPA.
I would greatly appreciate if you could explain it in the context of the Current and Future political situations and its implications.

Thanks in advance.