Partying serious is much different than partying hard. Partying serious is the much more sophisticated version of partying; it is to keep classy company of the same gender (ladies and gentlemen), whilst in robes, basking in presence of leather bound books, a fireplace, cigars and/or pipes, and of course fine, fine cognac and/or wine.
"We bring the girls in later." Brandon Boyd

The interview where "party serious" can be clearly explained is located here:

http://youtube.com/watch?v=qERBi6CeDs4

start at 2:06, ENJOYincubus
by Space Wrangler July 23, 2008
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