Transition-metal dichalcogenides (TMDs) uniquely combine topological electronic states realized without external magnetic fields with a strong optical response arising from long-lived excitons. Motivated by this confluence, we investigate an interacting fermion-boson system formed by coupling an exciton to a quasihole of a fractional Chern insulator (FCI) at filling fraction $1/3$. We introduce a kagome-lattice fermion-boson model hosting an electronic FCI and a mobile exciton whose dispersion is tunable from a parabolic band to a flat band. Using exact diagonalization, we demonstrate the emergence of exciton-quasihole bound states controlled by the repulsive electron-exciton interaction $V_{\mathrm{FB}}$ and the exciton kinetic energy $t_{\mathrm{B}}$. These states appear as low-lying levels in the fermion-boson spectrum, well separated from the scattering continuum, and arise despite repulsive interactions due to a residual attraction to the local charge depletion associated with a quasihole. Reducing $t_{\mathrm{B}}$ enhances this effect by favoring interaction-dominated binding. Our results provide a model description of moiré TMD heterostructures, including fractional Chern insulating twisted bilayer ${\mathrm{MoTe}}_2$ proximitized by excitonic TMD heterobilayers, where we estimate exciton-quasihole binding energy scales of 0.8–1.2 meV, placing these effects within reach of photoluminescence spectroscopy.

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• Anyons
• Bound states
• Chern insulators
• Excitons
• Fractionalization
• Quasiparticles & collective excitations
• Topological phases of matter
• Moire materials
• Transition metal dichalcogenides
• Twisted heterostructures