Let's see here. In the original game Yuffie was 16. In Advent Children Yuffie was 18. In Cerberus Yuffie was 19. And if their is indeed going to be another game Yuffie will more than likely be in her early twenties (probably 21 or older). I betcha she will be hanging out in all kinds of bars, drinking all kinds of beer, and dating all kinds of guys. She seems like a future party girl type to me. Vincent should date Shelke. She seems like she will be a little more settled down as a young adult than Yuffie will be.

Anyways I hope if they do continue to make more games they begin aging the characters so they look the age they are now supposed to be (and no longer look the age that they were in the original game). Yuffie was supposed to be 19 but still looked like the 16 year old we knew from the original game (not a big deal now as it is common for 16 year olds and 19 year olds to look physically similar to eachother). But in future games where Yuffie is supposed to be 25 or older I wouldn't want her to still look and act like a 16 year old.