These are teens and young adults at best - not really mature! Baby faces, no wrinkles, and no, well, sagging. :/ There's even a school outfit in there.
I got really excited when I saw the title, because there's a lack of any non-teen VN-style sprites out there, and was then a bit disappointed. As someone in their mid-thirties, it's very hard to find assets that represent the age demographic I'm in.
That said, it's still very cool that you're releasing free sprites for people to use in their projects - and a lot of people will get use out of them. Just a kind request to maybe tweak the title a little.
And, you know, apologies for being a grumpy old person.