Once upon a time people from another universe where magic was commonplace travelled to our world. Though many returned home some stayed and some bred with the locals. Thousands of generations later people with limited magical abilities manifested. These groups with a common power became "Magi-Clans". These days most Magi-Clans are large families with old money and a lot of influence, and actual magical power that they keep to themselves.
Ace Spellbound, family black sheep, believed doing the right thing and doing what made him happy was more important that maintaining the traditions of a self-centered modestly wealthy family of magicians. Ace used his power to become a hero, donning the mantle The Ace of Spades. Ace loves theatre, stage magic, men, and media tropes, which is sort of in opposition to his stodgy conservative wealthy family of doctors, lawyers, and CEOs. Ace and his sister Hannah become two of the 20 founding members of the first superhero team, The League of Heroes
Hannah Spellbound, lawyer wannabe and Ace's younger and more studious sister by 7 years, she took to spending more time with Ace whom she is close to while still studying under the ideals of her parents. She lives with Ace from time to time under the guise of spying on him for their family. Hannah, wanting to learn more from her brother, took on the mantle of Hearts. Her perspective can be described in this quote from her: "I've always been taught that the law is always right, that vigilante justice is wrong. But my brother taught me it's worse to do nothing when you could have done something."
Dickson "Dix" Spellbound is Ace and Hannah's uncle, a club owner and former Marine with a big heart. When Dix's brother kicked Ace out, Dix took Ace in, never having been on board with the family history of shadiness. He doesn't become a superhero immediately, only after coming out a few times to help his niece and nephew, and eventually he joins the UN-run superhero initiative, Heroes U.N.I.T.E.D. The more straightforward Dix took on the mantle 10 Club.
Finally there's Jackson Spellbound, the kind, handsome, perfect, and dashing twin cousin to Ace (born on the same day, not actual twins) who is naturally better at everything Ace is good at. After Ace defected from the family, Jack was to be groomed as future head of the family. Jack, while complicit in his family's ways, also harbors no ill will towards his family at all and naively believes He and Ace can get along as family. Ace is too clouded by jealousy and resentment to accept that. While Jack does not participate much in heroics, he has offered himself to be Ace and Hannah's ally under the name The Jack of Spades, and eventually becomes a reserve member of the League of Heroes known as the League of Allies.