“that's my kind of book!”
My kind of … means the type of thing I like. That's my kind of book! expresses approval. The same pattern works in my kind of town.
A2-36 / CEFR A2 / EPISODE 36
Recommending a good book
SceneAt a café. Frank recommends a book he has just finished.

WORDS & CONTEXT
My kind of … means the type of thing I like. That's my kind of book! expresses approval. The same pattern works in my kind of town.
Gotta represents a casual pronunciation of got to, and have got to means "must" (see A2-24). But when recommending something like a great book, it becomes a strong recommendation: "You really have to read it." Frank is not giving Tina an obligation; he wants her to enjoy a book he loved.
Sign means to write your signature, and a contract is a formal written agreement. Just sign here. means "Sign right here," and by Friday sets the deadline. It is a joke based on Frank's thoroughness: he has prepared a contract with a return date just for lending a book to a friend.
"A scientist learns from data." The "data" Frank means is the last time Tina returned a book late. Based on that, he wants the return date confirmed in a contract this time. The humor is that he brings a scientist's reasoning into everyday lending between friends.
In pink ink means writing with pink ink. Tina accepts signing the contract, but insists on her favorite color. The small punchline is Tina adding a condition of her own to Frank's stiff procedure.