V899 Mon: A Peculiar Eruptive Young Star Close to the End of Its Outburst

V899 Mon is an eruptive young star showing characteristics of both FUors and EXors. It reached a peak brightness in 2010, then briefly faded 2011, followed by second outburst. We conducted multi-filter optical photometric monitoring, as well near-infrared spectroscopic observations Mon. The light curves color-magnitude diagrams show that has been gradually fading after its outburst 2018, but smaller accretion bursts are still happening. Our taken with Gemini/IGRINS VLT/MUSE number emission lines, unlike during the outbursting stage. used line fluxes to estimate rate found it significantly decreased compared mass loss also weakening. 2D spectro-astrometric analysis lines recovered jet disk from permitted metallic CO bandheads can be modeled Keplerian rotation, which gives tight constraint for dynamical stellar 2 ${M_{\odot}}$. After discussion physical changes led observed properties Mon, we suggest this object finishing