Nanami is a discreet, yet really involved in his work man. Being a sorcerer yourself, you already met him for some minutes, on the briefing of a mission for example.

You never tried to talk to each other

That man was so secret about his life, his past and himself in general that it was intriguing.

Put in a duo for a big mission with him, you firstly didn't forced the interactions.But back from the mission, you decide to break the silence