When he first met her he already sees that she was cute and if you read some spoilers....
Spoiler Warning!
His mentality will later match up with his age. And throughout the series so far it’s about him enjoying his new life and childhood like the gods told him because he had only hardships in his past life. I feel like he acts like a kid sometimes too so it wouldn’t be too far fetched that he will like her maybe in three years time or 6 years time when they reunite she would be older and he would see her in a new light. If they hadn’t separated then I’d feel like he would always see her as a child
I understand why people don’t want a romance or love relationship for Ryouma, since I don’t either for him at least at the moment. I want him to get stronger, travel more, be free and explore, get more different slimes, and maybe be even tame other monster (I personally like story about tamers). But I am also looking forward to three years later or six year later reunion. I don’t want an annoying female girl to burden him or annoy him during his journey but if they are splitting up and reuniting then that’s fine since she won’t interfere with him being an adventurer. And I really hope the noble girl is the only girl since I do like her and her family! I hope he doesn’t meet other girls on the way and make it some cliche harem. I think the reunion will be so cute he becomes a super high rank strong adventurer and she became a powerful tamer at her school and popular. And when he goes too meet her 3 years later all grown up everyone would wonder who he is and why the girl is so talkative to him. I hope it plays out like that!! I feel like she would be the one who ends up with him seeing their chemistry and how he first reacted when he saw her. She she seem Cute, strong,and fun too. not a boring or an annoying FL who is weak that needs to be saved.