I've been thinking a lot about it all and I'm really considering putting together a short story to make a manga of it pretty soon. I want it to be really good so I might be working on it for a little while but I'm definitely going to create it as soon as I get the chance. for age of the characters, I figured when i first created them, Ayano is about 9 and Mika about 12. I'm really glad you like my characters and that you see those characteristics in them. outgoing and shy is pretty much how I imagined them when i first created them
as for why their still in diapers, it'll all be explained in the manga... as soon as I figure out why myself. Lol btw Ayano is personally my favorite character. just saying