Fofana admits the pair have quickly form an on-field understanding.
He said: "On the pitch it’s simple – I know him, he knows me and every game is a little bit better.
"We don’t need to talk too much. I feel good with him, he feels good with me.
"Away from the pitch we have a very good relationship. We are not just teammates, he’s a friend, my guy."
Fofana also discussed the impact of manager Enzo Maresca this season.
He told chelseafc.com: "We have a lot of meetings and watch a lot of videos to see the plan.
"We started in pre-season. First training session of the season he told the team what he wants and it is good. The style is good for the players we have. It’s offensive football. It’s very good."
He continued: "When you want to win titles and want to win every weekend, you focus on the little details. This is the difference between a good team and a big team. He explains every day in training that the little details are very important."