You have to go through the whole game and ALL their banters but by the end it's totally clear that both really respect each other. So unless you have a romanced/bff Inky for Solas - Cassandra is probably the most important person to him in the group.
Umm... *stealthily puts Cass/Krem fic ideas in trash*. Probably would have accidentally done something offensive anyway.
Anyway! Cassandra and Solas, they're two mature adults... with interests... and, stuff. They could talk about... What do they have in common again?
Screw it! Solas/Lavellan, Cass/Krem, Iron Bull/Leliana!
She's an exhausted John Le Carre style spymaster. He's an exuberant shirtless version of Ian Fleming's "blunt instrument". But when the two meet a divergence in the spy fiction genre nearly a century old will be crossed!
See that's the thing about you Solas thread, you're the only place where I care about the story of DA:I. Everything else is just post-structuralist tomfoolery and finding overly complex jokes.