Ooh! Alright, let’s take a look at Twistfell…. (You might know some of this, Fresh, but I’ll try to expand on it a bit.)
Blackberry prefers “unhealthy” foods. Sweets and greasy foods are his mainstays. He specializes in comfort food, particularly mac ‘n cheese, but he’s also a very good baker. (That’s why he’s chubbier than both Blue and Razz.)
Twist is more health conscious, but he’ll pretty much eat whatever Blackberry puts in front of him. Both of them enjoy puns, since neither of them are prone to wearing them out, though Twist is generally funnier than Blackberry.
And…(very slightly) NSFW here…but Twist is submissive in bed. He very much prefers to be controlled and directed. (So much of the time, he feels out of control and uncontained. Having someone else take responsibility is a relief for him.) Of course, you have to earn his trust and submission. He doesn’t just sub for anyone.