When Jenkins is in the basement and they are about to play the D&D game there is a clipping of an article from Sarina Bhonsle, who was the reporter in the episode And the Disenchanted Forest (2018).
This is the most Jenkins-centric episode so far, with the character on screen for the most time to date
'Asmodeus' appears in various Mythology outside "The Librarians." "The Librarians" created their own mythology of his capture and escape. More interesting, Asmodeus appears in Dungeons & Dragons game Jeff and his friends have played. Meaning, Asmodeus has a mythology in the real world, The Librarians and DND (Dungeon & Dragons.)
Jeff's friends refer to playing the fifth edition of D&D, which is (as of 2021) the most recent edition. The Monster Manual Schmidt holds up is from this edition.