Soft robotic grippers have an advantage in grasping objects with various shapes as compared to conventional rigid grippers. Soft grippers have been researched to hold objects which are fragile. Recently, researchers have utilized the jamming effect using particles, which makes stiffness varied to hold the objects tightly. In this paper, we propose a lip-inspired soft robotic gripper. This gripper is motivated by animals' oral structure, especially from lips. Lips have various functions: holding, re-grasping, sucking in, and spitting objects. This gripper especially focuses on the functions of holding and re-grasping. The lip-pouch is fabricated including granular particles inside for passive particle jamming. This paper describes how the gripper is motivated by lips with explanations of the anatomy and functions of the lip. An explanation of the passive particle jamming effect follows. We validated the capability of the lip-pouch of the gripper with various objects through experiments. Moreover, we demonstrated re-grasping objects with this gripper.