libpaq is a LIBrary for Parsing And Querying RDF data in Turtle format. It is used by lv2peg. It is not specific to LV2 data, you can use it for any RDF, but you probably don't want to - there are other RDF libraries that are more efficient.
libpaq requires the Boost headers to be installed when building it (particularly the Boost.Spirit recursive descent parsing framework), but there is no runtime dependency.