Hello,

I am looking for any manga with a romance where at first one of them is a kid and the older person is like 18, and their relationship is completely platonic, at first. Like an 'older brother' figure

Then I want there to be a timeskip, like the kid grows up to be 20 years old and meets the older person again, and somehow the relationship changes to a romantic one. it is important that the younger person hasn't had much contact if any with the older person while they were off growing up. Maybe they went on a journey or went to boarding school. I would prefer the younger one to be at least 19 when the romance starts but it's not super important.

i can think of miriam and the memoirs of a geisha book that might fit. Vampire/immortal characters are fine. It doesn't matter what the gender of the older/younger one is. Thanks everyone!

Hajimari No Niina

Kore Wa Koi No Hanashi

Dangan Honey
The heroine is a preschooler at the start of the series...

and at the end of the manga she did grew up into a fine young lady - saw it in the raws...
The scanlating group didn't drop this manga and I think there is 2 or 3 chapters? left to translate...
So you might wait up a bit...

Baby Love
My Fair Neighbor
Mikami-sensei no Aishikata
Miman Renai

"The world is a dangerous place to live, not because of the people who are evil, but because of the people who don't do anything about it." - Albert Einstein