And, yes, the sheer intoxication that comes from belonging to a crowd that has suddenly found its voice, and which demands to be heard.

这不是完整的句子，而是名词the sheer intoxication后接that定语从句。其中a crowd后接并列的定语从句，that..., and which..., 第二个定语从句通常用which引导。crowd视为一个整体时，关系代词用that/which, 不用who。