Ace’s first impression of Deuce comes during the opening ceremony when he predicts that they’ll “get on like oil and water” for how serious Deuce looks.
Ace introduces himself to Deuce at the welcoming party for 1st-year students, where he tries to convince Deuce to sneak into the Headmage’s office. When Cater thwarts the plan Deuce backs Ace up when encouraged, despite having only just met him.
While the two are roommates our second time seeing them overlap is the following day when Deuce drops a cauldron on Ace in an attempt to catch him for the prefect.
Deuce then magically tosses Ace at the cafeteria chandelier in an attempt to catch Grim, resulting in the group of himself, Ace, the prefect and Grim being expelled from the school.
It is Deuce who insists that Ace apologize to Riddle for stealing the tart of Book 1, and when Ace stands up to Riddle during the unbirthday party Deuce is the only Heartslabyul student who supports him.
When Ace signs up to duel Riddle for the role of Housewarden in Book 1, Deuce volunteers to join him.
Ace and Deuce are also of the same opinion in Book 2 when they both seek to take advantage of Trey being too injured to participate in the spelldrive tournament to earn a spot on the roster for themselves, but when they both volunteer to join Ramshackle’s team for the exhibition match Deuce says that he is not like Ace and just wants to support his friends.
Deuce says he is not sure how he should feel about his taste in art overlapping with Ace.
They work together to come up with churro toppings during Port Fest, and show up at the school store together during New Year’s, signing up for Kamakura-making and shiruko.
Kalim says that Ace gets “bright and bubbling” (“It’s adorable!”) when he is with Grim, the prefect or Deuce, and when Deuce disappears during Halloween Ace says he is not exactly worried about him, but it is weird how it is too quiet when he’s gone.
Twisted Wonderland Reference Note 