Left panel: effective projected separation between the compact red component and its associated companion(s) as a function of the inferred luminosity L₅₁₀₀. The luminosity is measured using the NIRCam filter closest to rest-frame 5100 Å and converted to a luminosity using the source redshift. The top panel shows the companion fraction as a function of luminosity; we find a striking trend where the companion fraction increases with L₅₁₀₀, reaching nearly ≧80%–100% completeness for the most luminous LRDs in our sample. Right panel: the UV magnitude of the companion(s) (rest-frame 1500 Å) as a function of L₅₁₀₀, indicating that companions associated with these high-luminosity LRDs are themselves significantly brighter in the UV.