The most effective way to report CSAM globally is through the National Center for Missing & Exploited Children (NCMEC) CyberTipline . They coordinate with federal law enforcement like the FBI.

Note that Nippyshare and related file-sharing services (e.g., Nippybox, Nippydrive) have been under investigation by Ofcom for failing to comply with duties to protect users from illegal content. Context on the File

It is a portmanteau of "hardcore" and "hurt," used specifically for material depicting the infliction of pain and torture on children. Possession or distribution of this material is a serious criminal offense.