User blog comment:B214/Talk About What You Want! 3/@comment-82.178.232.41-20150713070409/@comment-110.22.99.149-20150715122706

Rias is ment to be 18, as for the aging thing i seem to remember that devil kids age like human kids so they can grow up to defend themselves quicker, it's when they become young adults that's when their bodies change to age very slow.