In the real world, Neji is an honorable man who thinks peeping is a disgraceful act that he attempts to prevent Naruto from engaging in. However, in the alternate reality of the Limited Tsukuyomi, everyone's personalities are completely opposite of their real counterparts. In that sense, Neji is a fan of peeping on women using his Byakugan, and so Neji is essentially a "pervert" in the genjutsu world.