A Denizen that watches the Front Door of the House. He and either Saturday's Noon or Dusk are old adversaries (see Saturday's Dawn, Noon and Dusk). Recently, after the end of the Drowned Wednesday and the rest of Sir Thursday, he has been slightly wounded, due to constant troubles at the Front Door. He wields a sword of blue fire which is described in the fourth book, Sir Thursday, in his battle against Saturday's Dusk to aid Suzy. In Lady Friday and Superior Saturday the Front Door has been ordered shut to Arthur and his allies, Dame Primus tells Arthur that the Lieutenant Keeper has appealed to The Court of Days for the Front Door to be reopened. He is a reference to St. Peter, the gatekeeper of Heaven in Christian tradition. Arthur wishes to promote him. In Lord Sunday he is heavily wounded and passes his sword to Leaf, who becomes the new Lieutenant Keeper of the Front Door. Later on in Lord Sunday, Leaf accidentally gives her sword to Lieutenant Fred (from Sir Thursday), making him the Lieutenant Keeper. It is unclear if Fred keeps this position after the destruction of the house.