HD 154391 is an orange K-type dwarf (about 2.07 solar masses, 4,909 K, 8.56 solar radii), 101 light-years from Earth. HD 154391 b is a 9.10-Jupiter-mass companion, with an orbital period of 14.1 years, at 7.460 AU from its star, on an eccentric orbit (e ≈ 0.20), discovered in 2023 via radial velocity. The planet betrayed itself through the star's reflex motion — a technique that first revealed worlds around Sun-like stars in the 1990s and remains a workhorse of exoplanet discovery. The planet's marked eccentricity suggests past scattering events or perturbations from unseen companions.