A sixth form dropout from Northamptonshire is being hailed as the next EL James, after her Fifty Shades of Grey-style trilogy of erotic fiction shot to the top of the US bestseller charts.

Jodi Ellen Malpas, 33, worked for her family's building firm and for years wrote in her spare time. She recently gave up her day job when her self-published book, This Man, topped the US ebooks chart.

It is the final part of a trilogy, the tale of an affair between aristocrat Jesse Ward and Ava O'Shea, an interior designer. Its publication last week caused a surge in sales of its two companions, with the books taking all three top spots in the Publishers Weekly iBooks chart.

This Man is also the top seller in the Amazon erotic fiction chart.

Malpas, who lives in the Midlands with her family, is now cutting down the e editions for publication in print and preparing to meet her legions of fans at a writing convention in LA next month.

She told the Sunday Times her parents were initially worried when she would lock herself in her room for hours typing away as a youth.

"My mother, Lorraine, thought I was ill or something. Now she is my PA, dealing with all the fans and stuff, but I am still not letting her read the book - it's too much for her!"

Fifty Shades of Grey and its two successors, Fifty Shades Darker and Fifty Shades Freed, sold over 70 million copies worldwide after being self-published by London-based EL James. A film version is currently in production.

Rumour has it that Twilight duo Robert Pattinson and his estranged partner Kristen Stewart could co-star.