One that's got one of those Mesh Backs? One that doesn't have a too long of seat area because I'm small??

I'm looking to replace my current Chair with something that Won't hurt my back, and also isn't big enough for me to sit crosslegged because my current one is waaay too big for me. I can sit cross-legged on this current one, My Legs don't reach the edge where my knees bend. XD SO Yeah, an office chair that fits a smaller person, and doesn't hurt my back.