In 2005, Koj trained as an investment analyst, writing reports: part detective, part journalist, part judge.

In 2010, during paternity leave, he took up a new hobby and began writing a food blog.

In 2013, he began writing recipes and contributions for food and lifestyle magazines.

In 2017, he opened his first restaurant in Cheltenham.

In May 2020, during the height of Coronavirus lockdown, his first book “NO sushi” was published by A Way With Media.

It documents his early life and experience of opening a restaurant, explains why only 10% of restaurants in Japan serve sushi and showcases some of the dishes that have helped his restaurant win awards, national reviews and public acclaim.

He is a member of the Guild of Food Writers.