Stardust Accelerator - How do these "New Bonus" points work?

Beating other duelists garners you points you can spend on new packs, and the amount of points depends on various things that happened during the duel.
One was "new bonus" and I initially thought this was the bonus you get from beating any given character for the first time, but then I got that bonus twice from one guy.
What is this bonus, exactly?