TW: discussed homophobia and mentions of suicide in this chapter.
Not going to TW for "slash pairings" because I don't need to in this context

"Arcturus!" Gellert exclaimed in delight, opening his arms for a hug. "It's great to see you, old friend!"

Arcturus accepted, and returned, the hug stiffly and formally, acting as Sirius had always remembered him. "The pleasure is mine."

Gellert holds his friend at arms' length, clapping his shoulders, grinning and staring at him. "Merlin's beard, Arc, you've gotten old."

Arcturus didn't even crack a smile. "So have you, Gellert. It's been several decades since I last saw you."

Gellert's face didn't falter. "And yet we could still woo whichever ladies we want, right Arc?"

Still no expression change. "I suppose we could."

Gellert suddenly turned somber. "I am truly sorry to hear about Reg, Arcturus. I really liked your brother."

"So did I." Arcturus' face almost betrayed emotion for a moment, but it returned to its natural state, which made him seem irritated at the world at any given moment.

"Arc… What happened to you?" Gellert's eyebrows furrowed, and his hands slipped from his friend's shoulders to his hands, bringing them up to chest level and holding them comfortingly. "You're not nearly the man I remember."

"He's always been like this." Sirius cut in, and both men looked at him: Gellert in surprise, and Arcturus in a mix of guilt and anger. Sirius maintained eye contact with Gellert, not daring to look his grandfather in the eyes. "So long as I can remember, this is exactly how he has acted my entire life."

"What happened, Arc?" Gellert repeated, looking back at the man he used to know.

Arcturus' angry face turned to Gellert and grew colder. "Did you invite me here to interrogate me, Gellert?"

"Invite you? I didn't invite you." Gellert said sincerely. "I had no idea you were coming."

"I invited you." Sirius admitted, and the men looked at him again. "I put Gellert's name on the invitation because I knew you wouldn't come if it had been mine."

"You're right, I wouldn't have." Arcturus spat. "You have some nerve inviting me here, boy, after the grief you put your parents through, driving them to madness!"

"That I put them through?!" Sirius countered, raising his voice, forgetting about Luna and Harry on the couch. "What about the bullshit they put me through? The years of abuse and hatred, the slurs and the fists and the yelling and the curses, and not to mention what they did to me when they found out I was bisexual!" Sirius' voice cracked, and he broke eye contact with his grandfather to look at the carpet.

"Wait, what?" Arcturus blanched. "What did they do to you, Sirius?"

"I…" Sirius shook his head, tears forming in his eyes. "I don't want to talk about it."

Arcturus took his hands from Gellert's now vice grip and stepped over to Sirius, putting one on his shoulder and one on his cheek. "Sirius, look at me."

Sirius did, and for the first time in his entire life, he saw pity and affection in his grandfather's face.

"I had no idea what was going on, you must believe me. I never raised my son to lay a hand on his children."

"Father never hit me." Sirius stated truthfully. "It was only ever Mother, and it was only ever me. Mother never touched Reg. But Father was still ruthless and cruel, and he may as well have hit me for how much he verbally abused me."

"Oh, my boy, I am so sorry."

Sirius could never recall getting a hug from his grandfather, even as a small child. But somehow, being in Arcturus' embrace felt familiar and safe, much like James' parents had felt.

It broke him.

Sirius started sobbing into his grandfather's shoulder, and Arcturus rubbed his grandson's back as he murmured assuring words into his ear.

To Arcturus, it was just like comforting his brother Regulus. Their parents had been severely abusive, and Regulus was a rather fragile boy who would cry at any provocation. He didn't want that to ever happen to someone he loved again, and had never hit Orion or his siblings or allow them to get violent with each other. He had never seen Orion or Walburga's abuse towards Sirius, and hadn't even seen the signs. He had, however, heard Orion and Walburga's complaints about Sirius' behaviour, and had seen for himself how angry and rebellious Sirius was.

When Sirius was born, Arcturus had just lost his brother, and would soon also lose his beloved wife Melania to a rather nasty bout of Dragon Pox, which had surprised everyone considering most deaths from Dragon Pox were of wizards much older than they were. Arcturus was a hurt and grieving man, and Sirius' deviant, rebelling behaviour right from the very beginning was angering for him, so he preferred to keep his distance to avoid hurting the boy. He knew that because of his upbringing, he had violent tendencies when he was pushed over the edge, and he had been living on the edge since Regulus died. Arcturus then lost his sister Lycoris when Sirius was five, and his closest living relatives were his son and grandsons, who no longer wanted anything to do with him. Sure, he had his daughter Lucretia, but ever since she married that Prewett boy, she had been very distant, refusing to speak with her brother and by extension her father. Even worse, he lost both his grandson Regulus and his son Orion within a year of each other. Walburga had claimed to Arcturus that Sirius was to blame for the heartbreak that killed Orion, because he had said horrible things to them about Regulus joining Voldemort, and had been part of the reason Regulus withdrew from the family when he joined, which caused Orion a large amount of mental anguish by losing his favourite son even before he died.

Hearing the news of their deaths, Arcturus withdrew, became introverted and angry, and hadn't seen a living soul that wasn't his single remaining House Elf in years. He resented Sirius for being the reason he no longer had a son or the boy who so resembled his namesake, but he had never had any reason to believe that Walburga was lying to him.

Until now, anyways.

He had never realized until now how much Sirius actually resembled Regulus just as much as little Regulus Junior, as Arcturus had called him, had done. Junior had been a sensitive boy much like Regulus, and Arcturus had suspicions for years that Junior would eventually come out as a homosexual just like Regulus had. That had been a major point of contention between Arcturus' parents and their three children; Arcturus and Lycoris were supportive of their brother no matter how he wanted to live his life (honestly, he always assumed that Lycoris was also a homosexual, but she never said anything and he never felt it was his business to push her), but their parents were furious and nearly disowned him. It was only when Arcturus threatened to disown himself, which would have left his parents with no heir, that they let up somewhat. However, they were rather vocally boastful about having had Regulus' lover killed shortly after he had stated his intent to move to a place where they could marry. It broke Regulus, and he had killed himself eight years to the day after that.

But hearing that his own son had been so horrible to Sirius, especially about Sirius' sexuality, made Arcturus feel more protective and more angry than ever before.

"My parents did the same things to us." Arcturus admitted out loud, and Sirius' sniffling stopped, and he looked up at his grandfather in surprise. "They were terribly abusive, and they were even worse to my brother when he admitted to his homosexuality."

"Wait, great-uncle Regulus was gay?" Sirius repeated in surprise.

Arcturus nodded.

To Sirius' surprise – though, thinking about it, he really shouldn't have been surprised – Gellert also nodded. "I remember him telling me that he was going to tell his parents, and I remember how horribly it went." Gellert let out a grim laugh. "I felt so angry for him that I offered to kill his parents for him."

"Oh Merlin's balls, Gellert!" Arcturus exclaimed. "You were the friend who offered to kill our parents? Reg wouldn't tell me who it had been, but it always brought a smile to his face to think about."

"I almost wish I had. But it delights me to know they're already dead anyways."

Arcturus nodded. "Father died in 1952, and Mother died the same year Reg did."

"What even happened to Regulus?"

Arcturus drew a deep breath. This was going to be a very difficult story to recount, especially to Gellert.

Before he could begin, a cooing sound came from the couch, and both Gellert and Sirius suddenly remembered that Harry and Luna were still there.

Gellert scooped up the babbling Harry in his arms and presented him to his friend. "Arcturus, meet Dorea's grandson, James' boy."

Arcturus gasped. "Merlin, he looks so much like Dorea! I see Charlus in there, but he is definitely part of the Black family." Then he sighed. "I miss Dorea terribly."

"Were you close with her?" Sirius asked.

Arcturus pursed his lips. "We were close at one point in our lives, when we were young. She was my favourite cousin. But, among other differences, we were rather divided about the Dark Lord for a long time. When he killed her I began to see how wrong I was, and it only escalated once Junior died."

Leaning out of Gellert's arms, Harry reached for Arcturus, being reminded of both his father and of Sirius. "Grampa?"

A/N: I had something else planned for this chapter, but the backstory got away from me and it'll have to wait til next one. I'm not sorry ;)