Bits I can recall involve a main female character named Sora, a school with some sort of weird VR system, I think, and the main character is the only girl in the school who can use the system; extra note, only males could use the system otherwise, and the was something involving certain girls in the school turning into weapons... Also had some sort of reincarnation plot at some point.

Is it Shitsurakuen?

...Hop!

I'm definitely not one of those people who keep in their head all the names and plots of the manga that they read and the anime that they watched, but I'll assume that you "Absolute Duo"