I have a Japanese Pistol Shrimp. Also have a Yellow watchman Goby. Waiting for them to find each other and pair up which is awesome if/when they do. The shrimp digs a burrow and the watchman stands guard at the entrance. If a threat comes near the watchman wiggles his tail which the shrimp can feel. They can/will live together permanently.

Several Gobys and several types of Pistols will do this. If you don't have a shrimp goby and it is a Pistol shrimp you should get one.