Grench was a Bolian male and a Starfleet officer who served on the USS Voyager and held the rank of ensign.

In 2374, Voyager was bombarded with radiation from a white dwarf star. Ensign Grench was serving at the security station on the bridge when he suddenly collapsed and had a seizure. He was taken to sickbay where his body lost cohesion and he "melted" until nothing was left of him but a sticky residue. (VOY - String Theory novel: Cohesion)