Upper panel: Narrow-band image (25 Å wide in the observed frame) centered on the redshifted [O III] λ5007 extracted from the KMOS datacube. The QSO dominates the emission, but a weak source is detected at the location of Jil. Lower panel: Aperture spectrum (black line) within 0.″5 radius centered on Jil zoomed-in to the wavelength range covering the redshifted Hβ and [O III] λλ4960,5007 lines (vertical dashed lines). The green line represent the error spectrum (offset by −2 × 10⁻¹⁸ for readability) to highlight the position of sky lines. The best-fit model with a fixed [O III] doublet ratio is shown as the red line.