They would probably be very surprised at first. After all, they might not have expected to ever meet Luffy's mother. Then they would be excited to learn more about Luffy's past from her.
Well, his parents might be a bit shocked at first. I mean, Luffy's crew is full of such unique characters. They could start by testing the crew's loyalty to Luffy. And then, they might offer some valuable advice or even some special training. Like, if his father has some unique skills, he could pass them on to the crew to make them even stronger for their future adventures.
Well, Luffy might be completely shocked at first. His father has been this mysterious figure for so long. He could start asking a million questions about his family history, his father's adventures, and why he wasn't around. And his father might be proud to see how far Luffy has come in his own journey, achieving so much and making a name for himself in the pirate world.
The male protagonist was kidnapped and tortured because of his father's identity. He finally met his parents, but his father pretended not to know them. You can refer to the following novel title:
[Rebirth Massacre]
The story was about Lin Yu's father, who was an important historical figure but was kidnapped and tortured for some reason. After many years of hard work, Lin Yu finally found his father's whereabouts and successfully rescued him. However, his father pretended not to know him and was even frightened and disgusted by his appearance. In the second half of the story, Lin Yu and his father gradually developed feelings for each other, but their relationship was still very tense.
Adrien could meet other mysterious figures in the lair. It could be an old acquaintance of his father's who has been helping with his secret plans. Or perhaps he'll come across a captive who was being held by his father for some unknown reason.
The relationship might start with Naruto being a bit resentful at first for being left alone all those years. But as his father explains the reasons behind his actions, Naruto would gradually understand and they would form a deep bond. They could go on adventures together, with Naruto's father showing him secret places in the ninja world and teaching him how to use his Uzumaki heritage to its fullest. This would make Naruto even stronger and more confident in his abilities.
The crew would be really curious. They might see Luffy's father as a powerful ally. It could also boost their morale, knowing that Luffy has such a strong family connection.
She could be a former pirate captain herself. Maybe she was one of the most feared pirates in her time, and her skills and reputation were passed down to Luffy in some way, even if he didn't know it was from his mother.