"I enjoyed the time I had on loan with Forest and built up a good rapport with the fans," he told the club's official website.
"But the big thing for me is Billy. I know what he's all about and what he'll want to do and how he will approach things.
"And having worked with him and his backroom staff before it all fits.
"It ticks every box and although being at home and closer to my family is important to me as well, essentially my motivation was to come and play for Nottingham Forest."