Mesoscale simulations are performed to study the complexes between a dendrimer and a vesicle of amphiphilic molecules. In particular, the assembled structures and dynamics of these complexes are investigated by tuning vesicle size and the surface tension of vesicle membrane. Our simulations demonstrate that a dendrimer-based bulge containing amphiphilic molecules forms in the vesicle membrane when a dendrimer adheres to a vesicle. We find that vesicle size and the surface tension of the vesicle membrane permit effective accesses to control the shape change of the bulge structure with respect to various hydrophobic interactions in the complexes. The analysis for the energy of the vesicle reveals that the change of elastic energy induced by various densities of amphiphilic molecules in the membrane plays an important role in this bulge-shape control. Because both charged dendrimers and vesicles are effective nanodevices for targeted drug delivery, our findings shed light on the effective means of developing multitasking nanocarriers as targeted drug delivery platforms.