Multiferroic materials have attracted considerable attention due to the novel quantum phenomena, including magnetoelectric coupling and topological domains, which derived from the cross-coupling mechanism between ferroelectric and magnetic order. However, the discovery of intrinsic multiferroic materials exhibiting magnetoelectric coupling remains limited, as ferroelectricity typically originates from the d⁰ electronic configuration, while ferromagnetism relies on partially filled dⁿ state. Based on first principles calculations, this work demonstrate that electronic structure of PbTiO₃ perovskite can be engineered by introducing an Aurivillius-type interface layer, which induces localized magnetic moments at the interface. The results reveal that while the system retains strong electric polarization (up to 116.88 μC/cm²), the interfacial charge modifies the electronic occupation of oxygen atoms, thereby generating interface magnetism and enabling magnetoelectric coupling in PbTiO₃. Notably, this multiferroic state exhibits pronounced interface localization, with the magnetic moment decaying rapidly as the layer thickness increases. Importantly, the emergent magnetism is asymmetric, resulting in a net positive spontaneous magnetization of 2.0 μB, this observation indicates the emergence of ferrimagnetism at the interface. Furthermore, the interfacial regions manifest p-type conductivity behavior, exhibiting signatures characteristic of a two-dimensional hole gas (2DHG), the density of hole and charge carrier at the interface is several times higher than that in typical heterostructures. Overall, our work proposes a novel mechanism for designing multiferroic and offering a promising strategy for the development of magnetoelectric-coupled multiferroic devices.