A tailgater is a poem, specifically a couplet (a pair of lines) where the first line is supplied by a famous poem, and the second by you.
Most that I’ve ever read have been funny rather than profound, but there isn’t anything that says you can’t write a profound one if your sensibilities lie in that direction.
They do not have to rhyme. They do not have to be a particular meter. They just have to be two lines, with the first line famous and the second quite often infamous.
To an Actress, Regretting That Dessert
When in disgrace with fortune and men’s eyes,
have you ever considered Jazzercise?