Actually this is probably a good time to mention this. A lot of the time, anime characters appear nebulously young. I think this is an artefact of the style - everything is simplified and proportions are minced, and that makes ages hard to read sometimes.
For the most part, I don't pay much attention to a character's canon age - I am more concerned with how old they seem by their body.
This is for two important reasons: Some characters are super old but either due to style or the "vampire clause", they seem to have a child's body. Not really into that. Secondly artists kind of ignore age and proportions a lot and draw characters with whatever body they want anyway, so...
Anyway, if you hadn't noticed, I tend to prefer petite girls, and I know that combined with the nebulous hard-to-read age of anime characters can make some people shiver, so I err on the side of caution.
This is kind of the one part of this account that I do for the sake of the people following me rather than myself. I'm comfortable that I'm interpreting them as adults but I know others might not so yeah. Anyway, porn.