I must confess to having no idea who Margery Kempe was nor why she should merit this bench memorial close by St Margaret's church. An odd looking bench indeed, one might think it has the shape of a book falling open. And therein lies a clue. Mrs Kempe, I find, was a medieval Christian mystic who wrote a book, called rather unimaginatively, The Book of Margery Kempe. I say wrote but most think she dictated as she could neither read nor write. Margery, if we may be less formal, came from well-to-do Lynn folk and married well, had fourteen children (ouch!) and started having visions of Christ after the birth of her first child (as you might)... She went on a pilgrimage to Jerusalem, met up with the anchoress Julian of Norwich and ... there's obviously more to this woman, her "demonic torment(s) and Christic apparition(s)" and her book than I could possibly do justice to in this little digital scrapbook ... so you can find out more yourself with a quick exercise of your Google powers and if you really want to read the book, described as the first autobiography in English, then it has been transcribed from the only known copy in the British Library and is available on line here. And oh yeah, it's in Middle English, so watch out for synful caytyfs ...
And for your further delight I find the BBC have a podcast all about Margery Kempe but it does feature (Lord) Melvynn Bragg whose voice is not to everyone's taste.
Finally, I didn't try it, but that bench looks mightily uncomfortable.