Narcissa is a Queen
Until Severus had told him, Remus didn't know Narcissa was trans. She had apparently transitioned at some point before their first year. And, otherwise, there had been no way for him to know.
Not that Remus cared about Narcissa's sex or gender. Or anyone's for that matter. Still, he couldn't get it out of his head.
How nervous Severus was about telling his best friends his sexuality was startling. Remus had had his fair share of scary coming outs, but had never been as anxious as Severus seemed to be. Definitely not with his friends.
Remus wasn't blaming Severus, Lucius, or Narcissa for the situation. They were all obviously close, good, friends. It was society's fault, Remus thought.
Narcissa a bisexual trans woman, Lucius clearly comfortable with his sexuality(whatever that may be)based on his level of affection with Severus. And yet, there was still a chance they could be really horrid to him for this.
Not believe him because it was 'impossible' for a trans man to be gay. Think that Remus was a chaser who was just dating Severus for his body. Lucius may grow uncomfortable with the idea of him ever having hugged or kissed Severus because now he knew there was a possibility Severus was attracted to him(he wasn't).
It was unfair.
Remus didn't think they would do those things; hoped they wouldn't, but....It was always a possibility. He just wanted his boyfriend to be safe and happy and loved and supported.
Why was that so controversial?