Despite so many investigations on the WEC-breakwater integration system, the practical wave energy extraction efficiency still needs to be improved. Recently, using specially designed arc breakwaters to focus the wave energy to a certain area was found to be a feasible method. In this paper the integration strategy of setting a heaving WEC at the central of a semicircle opening of a vertical solid breakwater is investigated based on the linear potential flow theory, with a semicircle thin curtain wall set outside the opening to give protection on the heaving WEC. The boundary value problem is solved using the method of separation of variables and eigenfunction expansion matching, and the multi-term Galerkin method is adopted to handle the singularity at the thin curtain wall. After successful validation of the proposed theoretical model, a comparison study between the proposed integration systems with different permeability of the curtain wall is conducted, and the cases with a heaving WEC in front of a flat vertical wall and an isolated heaving WEC are considered as a comparison. Then a parametric study is carried out on the effects of the incident wave angle, the porosity, radius, and draft of the semicircle curtain wall, and the dimension of the heaving WEC.