We study the honeycomb lattice with a single magnetic impurity modeled by adding imaginary next-nearest-neighbor hopping $ih$ on a single hexagon. This Haldane defect gives a topological mass term to the gapless Dirac cones and generates chirality. For a small density of defects, Neehus et al. [Phys. Rev. Lett. 135, 126604 (2025)] found that the system's chirality reverses at a critical $h_c\approx 0.95$ associated with an unexpected tricritical point of Dirac fermions at zero defect density. We investigate this zero-density limit by analyzing a single defect and computing two experimentally relevant measures of chirality: (1) orbital magnetization via local Chern marker, a bulk probe of all occupied states; and (2) electronic currents of low-energy states. Both probes show a chirality reversal at a critical $h_c\approx 0.9\text{–}1.0$. Motivated by this consistency, we propose a defect-scale toy model whose low-energy states reverse their chirality at $h_c^{\prime }\approx 0.87$. Remarkably, the same pair of zero-energy bound states also generates the critical point $h_c$ in the full impurity projected T-matrix. Our results show how the chirality reversal produced by an impurity can be observed either in local probes or in the global topology, and suggest a possible role of the microscopic defect structure at the critical point.

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• Chern insulators
• Dirac semimetal
• Disordered systems
• Honeycomb lattice
• Green's function methods
• Single impurity model
• Topology