Warrington Munt was a Giff who had been serving on a Spelljammer (a magic-powered spaceship) that crashed into the sea some days out of Waterdeep. He was rescued by the Wafflecrew, and quickly assumed the first mate's position on board the Brazen Pegasus.  The Waffle Crew and the people on board the ship regard him with equal parts fear and amusement. Warrington was attacked by an intellect devourer and lost some of his short-term memory. Magnus took him to a church to get it restored. 
When the group arrived in Waterdeep, Warrington was separated from them for a time. He eventually found their new home and moved in with them. During a battle at the home, a barrel of gunpowder that he was holding exploded, but he survived the incident. 
It was eventually revealed that a mind flayer tadpole had infected Warrington during his battle on the illithid ship, which slowly transformed him into a mind flayer. He attacked the waffle crew and was slain by a lightning bolt spell cast by Strix. The heroes wanted to bring him back from the dead, but concluded that there was no viable way to do so.
The Giff are a race of humanoid hippo-folk who first appeared in the 2nd edition Spelljammer setting. They are mercenaries who have an an unhealthy obsession with weaponry, particularly muskets and blunderbusses.