What percentage of Monero pull requests so far have been made by Moneromooo?
Is Moneromooo the most active Monero developer?
How was did Moneromooo choose his name?
I dont know about the pull requests specifically, but here you can see overall activity of participants.
Moneromooo is the most active with 710 commits, second being fluffyponny with 285.
Moneromooo's work also looks very steady during last year and half.