"Nawazuddin is a very good man. I love him a lot. With him, I share a silent relationship. We can even sit in a plane without talking for three hours straight," he said on UTV Stars' show 'Yeh Hai Meri Kahaani'.
The 'Dev D' helmer said he is an introvert and often faces problem to express his emotions.
"I have trouble expressing myself where it is essential to," he added.
After the success of anthology film 'Bombay Talkies', Kashyap is currently working on his next directorial venture 'Ugly'.
"The most horrifying moment for me, worse than 'Paanch' being unreleased, was the re-release of 'Black Friday' in 2005 when I had got my first suit stitched for the premiere of the film.I wore that suit and headed for the premier.
"Just when I was about to leave my house I received a call. The film had got stalled again. Wearing that same suit I entered my room and didn't come out for three months. This has been my worst moment so far.