In order for humanoids to be able to achieve task-oriented behaviors with high responsiveness against instantaneous environmental or self-body changes, the realization of software adaptability is one of the key issues. For example, humanoids which interact with human at a very close distance have to respond to many contact events with outer environments, human bodies, or a self body during the interaction behaviors at the same time. In order to deal with such complex circumstances, behavior integration system is adopted in this paper. By introducing such behavior integration system, adaptability to many local events can be added incrementally. Also the analytically designed and slightly limited behavior modules can be accumulated for generating next richer behaviors. As such behavior integration system, ‘Parallel Evaluating Monitors’ is proposed. ‘Parallel Evaluating Monitors’ always run in the background of the normal task-oriented behavior, and it monitors the sensor changes and modifies the original motion trajectories if it's evaluated as a necessary one from monitoring results. In this paper, the implementation of the ‘Parallel Evaluating Monitors’ is described, and the implemented behavior integration system is applied to the different types of humanoids' interaction behavior for confirming the feasibility of the proposed system.