Quote Originally Posted by DarthEnderX View Post
Even much later in life they could still have an attachment to you that isn't completely rational.
That's called love. It's not completely rational, but it certainly helps a couple to stay together.

Quote Originally Posted by DarthEnderX View Post
That's why, if you've known someone as a child you should probably just...not. In general. Like, go find someone else. There's a whole world full of people out there. You don't gotta fuck family members, friends' partners, people you knew as kids, etc.

Again though, this doesn't doesn't actually apply to Rudy. Because he's actually in his 40s. But, again, they don't know that.
It's certainly sound advice in our world because if one is already an adult when the other is still a small kid, the age difference is pretty huge. That being said, Roxy didn't even recognise Rudeus initially, so you can hardly say she would have fallen for the child Rudeus and then only kept waiting for him to reach the marriageable age. Furthermore, it's not our world. I don't remember if it has been mentioned, but isn't it possible Roxy will still live much longer than Rudeus, not being a human, despite already being a lot older in absolute numbers? If I had to guess, she's still probably a young adult, just like Rudeus.

Since this series takes place in a fantasy world, you need to keep it in mind. If some non-human lives for 200-300 years, it's better not to limit them so strictly to what would be the common sense for humans, who might last 70 years in that world. Among Roxy's own people, a couple with 30 years of age difference might still live 200 years together, married. Though like I said, I don't remember if her kind's life expectancy has been mentioned.

Lastly, it would be pretty sad and even insulting for Rudeus if Roxy told him that since she knew him for a little while back when he was a child, she won't ever date him. Even though she didn't even recognise him as an adult, initially, and clearly saw him as an attractive stranger appearing to rescue her. It would be a clearly dishonest rejection.