I've been using Libby extensively lately, mostly catching up on graphic novels that I've been meaning to read. My city library is well-integrated with it and carries a great selection!
I feel like I've heard of other free online libraries that can be connected to through Libby (or at least through the old app, Overdrive). If I find some I'll add them here later.
I have never heard of a teen library drop-in centre, but I love the idea. With the decline of indoor malls, and especially combined with the brutal winters we have here, there are barely any free indoor spaces for teens or unhoused folk to spend time. Some cities have built beautiful megalibraries (my city is building one now!), and when I've visited them it's been remarkable how free you feel to just exist in the space.
I've been watching the anime based on this! It's really sweet, and the world-building is pretty interesting so far. I heard the LN was really popular, but I haven't read it yet.
Probably getting ahead of things a little, but it might be cool to set up a Bookwyrm community for literature.cafe one day! I started using it recently and I'm quite enjoying it.
Thanks for setting things up, I'll happily chip in for server costs whenever I can.