May Cassini was a New Human in a same-sex marriage with her wife Alice Cassini. They travelled on the Motorway together from when it was first opened to its closure in 5,000,000,053.
Whilst in the Motorway, May was a friend of Thomas Kincade Brannigan and developed hobbies of knitting and keeping a record of which cars came into the Motorway. Though she didn't intially realize it, when looking through her past records, she saw that no ambulances or police crews had been through the motorway since it closed, a fact which disturbed her. (DW: Gridlock)