Ah, I see. She was complimenting you. By telling you that you are "too innocent", she most likely meant that you seem like an all-around good guy. You are not like the other guys her niece has brought by.
She likes you so she is preparing you. Her and her family will corrupt you a little (they aren't as innocent) but in a fun way.
It could also be a little of "you're too good for her" but I don't think she meant it as an insult to the niece. I get the vibe that this is the way she talks to people.
So yes, she meant something by it, but it was nothing negative.
My honest opinion.
I got this feeling as well because I have heard similar things from other people and have said as much myself. I see it every semester as little innocent freshmen come onto Greek row and are exposed to whole new levels of debauchery. Things I have gotten used to seeing, things that have become normal to me. Some jump head first into the experience, others try to hold onto their “goodness” and “innocence”. I don’t share even a fraction of what I have experienced in my college years and what I do share is typically the “innocent” side of fun. Some things are just better off not talked about in the public domain even if they would make hilarious and awesome stories.
What has me so obsessed with the comment is I have not heard it for a while directed towards me and there are greater implications to being innocent that [MENTION=731]the[/MENTION] touched on. I kind of needed someone else to point out that negative truth of innocence to confirm the gut feeling I had on the comment. I do not think it was meant in that way as multiple people have pointed out and the niece knows I have a not so innocent side as well, you just have to get past the polite and serious wall I put up. But looking at the bigger picture and ignoring this one event is what is making me dwell on it more. This is why I was curious about how my personality is projected on this forum. I know online personalities are a bit different than reality because there is so much lost in translation, especially since I use this place as kind of an escape but there is truth there.