Stella Maeve's (Julia) real life pregnancy was written into the storyline.
The sex-ed advice on Dean Fogg's blackboard includes: if an enlargement spell lasts for more than 4 hours, call a doctor; however magical the creature, if it can talk, it can give consent; hexes are temporary, curses are forever; if using levitation, remember you will fall post climax; and don't use motion potion for lotion.
At 23:06 Josh refers to "Newt and Ripley" who are the two leading female characters in Aliens (1986).
Julia blames herself for being captured and the conditions of magic on Earth, because she appropriated Sir Effington's quest from whomever it was intended for.