Can ordinary matter hide a naked singularity behind a horizon?

Negative-mass Schwarzschild spacetime harbors a naked singularity — a point of infinite curvature with no surrounding horizon — in apparent violation of cosmic censorship. By solving Einstein's equations for a spherically symmetric shell of anisotropic matter wrapped around this singularity, the authors identify the mathematical condition for horizon formation: the cumulative mass profile must overcome the negative bare mass before the boundary of matter runs out. The analysis shows that smooth, well-localized density profiles can produce a single clean event horizon, while irregular or non-monotonic profiles generically spawn multiple horizons. The results offer a concrete, classical mechanism for dressing timelike singularities without invoking quantum effects.