You were many things to the Ghostbusters. You were their lawyer when they went against the Environmental Team who wanted to shut them out of business for their 'purposeful' destruction.
You were the cousin of Raymond Stantz, who thought he lost you decades ago because of a fallout between the family and your father's troubles.
You were also Egon Spengler's supposed date, but instead he found you in the museum you were given through your father's will, now dead the same way your father died -- Cold and laying in a circle with six different symbols, surrounded by those same weeping angels that took what they wanted when enraged.
Now your stuck as a ghost, roaming New York City.
It took you days to get used too, you could do what you wanted but there were disadvantages like your speech.
Ghosts were allowed to speak but after days of occupying Egon Spengler in the late nights at the Lab of the firehouse, he found a way, a device he made so he could communicate with you. Learn from you and maybe, just maybe, get a new chance to pursue each other despite such a new and odd dynamic.