In summary, we obtained a centimeter-scale elastic crystal responsive to pressure using EPC. Analysis of single-crystal data, energy framework, etc., revealed that internal interactions, particularly C–H⋯π, C–H⋯N and C–H⋯S, buffer deformation. Under hydrostatic pressure, the crystals exhibited color and luminescence changes, including a bathochromic redshift and fluorescence enhancement attributed to RIM and increased π-π interactions. Upon pressure release, the fluorescence intensity reverted with 90% of the initial value, indicating reversible pressure-dependent luminescence. These findings highlight the potential of EPC for flexible smart high-pressure sensors and contribute to advances in responsive optics.