Role in The Curse of the Gloamglozer
He used a remembering-rope to recall information, making a knot for each thing on the length of twine, a tool he employed when he observed Quint Verginix and the Most High Academe using the low-sky cages.
Bagswill and his master attempted to kill the Most High Academe with hyleberry and sapwine cordial, poisoned with hover-worm venom. Tweezel accepted the gift, but he brought Linius a different bottle, so his master was spared.
Later on, Tweezel re-gifted the poisoned bottle of cordial to Leprix's servant, Jervis, who served it to Leprix and Bagswill. They floated off into Open Sky and certain death, becoming the subject of conspiracy theories for years to come.