We propose a phenomenological framework for spherical, neutral, non-spinning ultra-compact, horizonless objects that mimic black holes for distant observers while avoiding a permanent trapped region. The key mechanism is a stochastic transparency micro-window process localized near an operationally defined quasi-horizon (effective boundary), which intermittently suppresses reabsorption of outward modes. We introduce a coarse-grained history-dependent state variable `Pi` encoding accretion-driven loading or stress in the near-surface layer that amplifies the micro-window mechanism. We define a BH-mimicking subclass by imposing that, in the quiescent macroscopic limit (`M >> M_*`, `Pi -> 0`), the coarse-grained Bondi outflux matches Hawking-like scaling `EPₒut ~ kappa/M²`. The novel content concerns stochastic, history-dependent mechanisms that satisfy this imposed mean while generating testable higher-moment signatures: a loading state `Pi` driven by recent inflow modulates higher moments of a stochastic micro-window process, yielding fixed-mass correlations in burstiness even when the mean leakage is observationally negligible. In bright sources, we treat observational proxy-events as indicators of boundary-state switching that modulates an already-detectable channel, not as direct detection of Hawking-scale energy packets. We emphasize invariant near-horizon structure using proper distance and redshift; a Planck-scale proper layer maps to a trans-Planckian areal-radius offset and yields logarithmically sensitive escape-time delays, motivating the stochastic boundary description. Finally, we articulate three operational perspectives—distant observer, infaller, and stored-shell (captured-layer) observer—consistent with the effective model.
Rodrigo dos Santos Marques (Mon,) studied this question.