Giant second-order hyperpolarizability (beta) values are exhibited by dispersible, hybrid organic-inorganic nanoparticles comprising about one thousand push-pull molecules intercalated between layered MnPS3 nanoslabs. Enhancement of beta is due to the parallel, ferroelectric-like arrangement of the chromophores within each nanoparticle. The chromophores spontaneously line up because they self-assemble as extended J-aggregates.