B Kͦ, MiniBooNE and muon g-2 anomalies from a dark sector

Belle II has reported the first evidence for B+ -> K+ nu nu over bar with a branching ratio 2.7 sigma higher than the standard model expectation. We explain this and the MiniBooNE and muon anomalous magnetic moment anomalies in a model with a dark scalar that couples to a slightly heavier sterile Dirac neutrino and that communicates with the visible sector via a Higgs portal. We make predictions for rare kaon and other B meson decays.