Cysteine protease that cleaves specifically after arginine or lysine residues (PubMed:22402587). May play a role in apoptosis (PubMed:22402587). Activated by Ca(2+). Localizes to RAB11-positive recycling endosomes. Specifically expressed in epimastigotes (at protein level). In epimastigotes, the unprocessed enzyme appears to be the main form (PubMed:22402587). Auto-processing is dispensable for catalytic activity towards small oligopeptide substrates (PubMed:22402587). Belongs to the peptidase C14B family.