In Book 2 Jack asks why Deuce’s group is chasing down Ruggie “for the sake of total strangers” and Deuce responds, “This is just a chance for us to score some kudos by catching the culprit.”
Jack says that he was doubting whether he could trust people who would suffer for strangers, “but it turns out you guys are total scum”.
Jack then insists on fighting everyone (“If I’m gonna trust you, I gotta size you up first”) and Deuce is delighted to “THROW DOWN!”
The two appear to reach some kind of understanding through the subsequent scuffle.
Jack and Deuce also overlap during Vargas Camp, where Deuce insists the track and field team follow Jack’s advice despite Jack’s insistence that he isn’t trying to tell anyone what to do, and they decide to start working together.
Jack goads Deuce into keeping up with him and Jack outright refuses to believe Deuce and Grim’s story about a monster in the mines.
Deuce explains he and Jack train separately but always end up competing if they happen to be exercising nearby one another, “So I’ll go in planning on a light workout but then end up in a full-blown competition.”
Deuce says that they don’t talk much as “Jack is something of a lone wolf”, but “We’re a lot alike in that way.”
During Halloween Jack confides his problems to Deuce despite his reluctance to to take Savanaclaw’s problems to other dorms, and in a vignette we learn that Jack will vent to Deuce as well, though Jack also tends to make disparaging comments about Deuce’s intelligence that Deuce does not appreciate.
Despite Deuce’s fondness for Crewel he steps up to protect Jack due to a misunderstanding of Crewel’s attempts to readjust Jack’s too-small uniform so that it will no longer restrain his movements when he runs.
Twisted Wonderland Reference Note 