In this work, We investigate a one-dimensional two-boson system with complex interaction modulation, described by the Hamiltonian: $$\hat{H}=-J\sum_{j}\left(\hat{c}_j^\dagger\hat{c}_{j+1}+h.c\right)+\sum_{j}\frac{U}{2}e^{2i\pi\alpha j}\hat{n}_j\left(\hat{n}_j-1\right),$$ where U is the interaction amplitude, and the modulation frequency α = (√5 - 1) is an irrational number. The interaction satisfies $U_{-j}=U^*_j$, ensuring the system possesses party-time (PT) reversal symmetry. Using the exact diagonalization method, we numerically calculated the real-to-complex transition of the energy spectrum, Shannon entropy, the normalized participation ration, and the topological winding number. For small U, all eigenvalues are real. However, as U increases, eigenvalues corresponding to two particles occupying the same site become complex, marking a PT symmetry-breaking transition at U = 2. This point signifies a real-to-complex transition in the spectrum. To characterize the localization properties of the system, we employ the Shannon entropy and the normalized participation ration (NPR). When U < 2, all the eigenstates are extended, exhibiting high Shannon entropy and NPR values. Conversely, for U > 2, states with complex eigenvalues showing low Shannon entropy and significantly reduced NPR, indicating localization. Meanwhile, in this regime, states with real eigenvalues remain extended. We further analyze the topological aspects of the system using the winding number. A topological phase transition occurs at U = 2, where the winding number changes from 0 to 1. This transition coincides with the onset of PT symmetry breaking and the localization transition. The dynamical evolution can be used to detect the localization properties and the real-to-complex transition with the initial state being two bosons at the center site of the chain. Finally, we propose an experimental realization using a two dimensional linear photonic waveguide array. The modulated interaction can be controlled by adjusting the changing the real and imaginary parts of the refractive index of diagonal waveguides. To simulate this non-Hermitian two-body problem, we numerically calculate the density distributions of the wave packets in a two-dimensional plane, which indirectly reflects the propagation of light in a two-dimensional waveguide array. We hope that our work can deepen the understanding of the interplay between interaction and disorder while stimulating further interest in two-body systems and non-Hermitian localization.