Jack Howl/Relationships

MC

 * During the events of Episode 3, he helped them confront Azul. And asked Leona to let them stay at the Savanaclaw dorm, when Azul kicked them out from the Ramshackle dorm.

Ace Trappola

 * On somewhat friendly terms as fellow first years, but thinks he could stand to make an effort in things

Deuce Spade

 * In track and field club together.

Epel Felmier

 * Classmates (1-B)

Riddle Rosehearts

 * Admires him.

Azul Ashengrotto

 * Is not fond of Azul due to his sneaky, dishonest ways (of course contrasting with his more honest personality)
 * They are however, shown to make quite the formidable tactical team with Jack's physical abilities and Azul's cunning and intellect as shown in the Happy Beans Day/Beanfest event story

Jade Leech

 * As with Azul he is distrustful of Jade and finds him further troublesome due to his cunning such as when Jade suggests to Yuu/MC to make a deal with Azul to free Ace, Deuce, and Grim in Episode 3

Floyd Leech

 * As with Azul and Jade he is distrustful of Floyd and finds him further troublesome due to his unpredictability as well his magical and physical prowess (of course including his unique magic "Bind The Heart")

Cater Diamond

 * From the same homeland.

Leona Kingscholar

 * Admires him

Vil Schoenheit

 * Both lived in the same neighborhood as kids
 * It is revealed in Main Story Episode 5 that they met as kids when Vil had just moved to the same town as Jack. Jack saved Vil from some bullies who associated Vil with the terrible villain he played on a TV drama claiming they were going to punish Vil on behalf of the hero of said show; a feat they claimed would be simple since Vil looked frail and easy to overpower. Before they got close enough to him, however, Jack lunged at the bullies who ran away frightened after seeing it's Jack. Jack asked Vil if he's okay, to which Vil replied that he takes boxing and fencing and did not need to be rescued. Jack apologizes, but Vil thanks him for what he did regardless, claiming he is used to "stupid kids that cannot separate fiction from reality". Jack tells him he doesn't have a TV so he doesn't quite get it, but the fact that he moved some kids into hating him this much must mean Vil is a pretty good actor. This seems to cheer Vil up, who tells him next time he'll make sure to play the lead so he can move those kids to tears with his performance instead.
 * They often go on morning jogs together.