Although we have demonstrated that RTP can be enabled through suppression of non-radiative decay due to the presence of hydrogen bonding between guest and host, it is not clear how the triplet excited state is so efficiently populated in TPA-CO2H given the large measured DEST of 0.53 eV in 2- MeTHF glass. To understand the origin of the large population of triplet excitons, we modelled the optoelectronic properties of the TPA-CO2H using density functional theory (DFT) at the PBE0/6-31G(d,p) level using ethanol as a solvent continuum model. The SOC matrix element (SOCME) between S1 and T1, !𝑆 ! #𝐻 % "#$ #𝑇 ! ' , is 0.20 cm -1 . An intermediate T2 exists, showing a larger !𝑆 ! #𝐻 % "#$ #𝑇 % ' of 0.78 cm -1 (Figure ); thus, this state can act as a bridge to populate T1 via intersystem crossing between S1 and T2. The orbital character of S1, T1, and T2 was investigated using natural transition orbitals (NTOs) analysis at the T1-optimized geometry. The results reveal that the S1 and T1 states of TPA-CO2H both show LE character, while the T2 state possesses a mixed charge-transfer (CT) and LE character (Figure ). The LE character of T1 is also reflected by the uniform distribution of the total spin densities (Figure ). Given that similar RTP behavior was observed in two structurally and morphologically distinct host matrices, we next probed whether such behavior would exist in other hosts capable of hydrogen bonding. We thus studied the photophysical behavior of 1 wt% samples of TPA-CO2H doped in granulated white sugar, edible gelatine, and paper. The TPA-CO2H/sugar and TPA-CO2H/gelatine composites were fabricated by drop-casting a methanol/water solution onto glass, followed by annealing at 80 °C for 30 min. The TPA-CO2H/paper counterpart was fabricated by drop-casting a methanol solution onto the paper, followed by heating at 60 °C for 10 min. All samples have similar steady-state PL spectra, with RTP at ~485 nm (Figure ). The composites using sugar, gelatine, and paper exhibit long tPh of 329, 132, and 234 ms, respectively. The gelatine-based film shows a higher FPh of 33% than that of 18% for the sugar-based film. The divergence in tPh and FPh likely stems from the difference in hydrogen-bonded supramolecular networks (Figures and; Table ). Figure shows images of the blue afterglow of the composites at 298 K after irradiation at 365 nm. Recognizing the simplicity and utility of enabling RTP using these host-guest systems, we then demonstrated the utility of the RTP from the 1 wt% TPA-CO2H doped films in PVA. Benefitting from the flexibility of PVA films, we produced multi-use afterglow origami (Figure , Videos S1 and S2) without affecting the blue afterglow, demonstrating the compatible processability of this RTP film.