Complex sentence: Thereupon, he says sarcastically that these masks are just that--and offers the mask of a sniveling coward to Emily, a miserable miser to Wilfred, a twisted buffoon to Wilfred Jr., and a self-obsessed narcissist to Paula.
Split into simpler sentences: Thereupon, he says sarcastically that these masks are just that. Jason offers the mask of a sniveling coward to Emily, a miserable miser to Wilfred, a twisted buffoon to Wilfred Jr., and a self-obsessed narcissist to Paula.