"I like being different," Flaherty told NJ.com.
She said her entrance one-upped her brother, who previously arrived at prom in a hearse, but didn't make use of a coffin.
Flaherty said she plans to enter Mercer County Community College's funeral service program after graduating high school.
"She just really took to it," said her mother, Susan Flaherty. "She thought it was an honorable thing and an honorable way to make a living."
A Florida teen didn't make quite as extravagant an entrance to prom, but her photos quickly went viral due to the matching dress she made for her dog out of the leftover fabric from her own gown.