One main element is the contrast. The contrast between the living world and the afterlife, which Beetlejuice represents. For example, a normal person from the living world might have very different values and ways of life compared to Beetlejuice. Another element is the supernatural aspect. Since Beetlejuice has special powers, it can add an interesting dynamic to the love story, like he could use his powers to create unique dates or protect his love interest. Also, the spooky and comical nature of Beetlejuice is an important part. His zany behavior and the spooky setting can make the love story both thrilling and humorous.
In a Beetlejuice love story, the element of the unexpected is crucial. It's unexpected that someone would fall in love with a wild and often obnoxious character like Beetlejuice. Then there's the element of transformation. The person who falls in love with Beetlejuice might transform from being afraid or disgusted to loving him. And the setting, which is usually a haunted place, plays a big role. The dark and mysterious environment of the haunted house or the afterlife realm sets the mood for the love story. It gives a sense of mystery and danger, which makes the love between the characters more intense.