This paper proposes an FBM-based endoscope model for real-time endoscopy simulation. This paper develops a storage scheme for a stiffness matrix of the endoscope model and employs a block LDL-decomposition for a FBM-based endoscopy simulation which is hard to achieve in real-time due to computational load. This paper uses a characteristic of the stiffness matrix that is symmetric and tri-block diagonal to reduce computational load. We store block diagonal and lower block sub-diagonal entries instead of storing the whole stiffness matrix. A block LDL-decomposition is employed to solve the stiffness matrix. A real-time FBM-based endoscopy simulation is achieved with an endoscope model with 100 nodes.