That's not edgy enough for this manga. The real answer is that Kaname is still alive. She has recovered, but she lost her memories. And her brother, Jun, is perpetually dating her. Either because he's gone mad and fell in love, or he is trying to keep her protected until he can kill Kyou.
Edgier Plottwist: She falls in love with Uruma all over again, and Jun, after witnessing this, falls to the deep end and joins Kyou. Kyou says some bullshit about "no matter how many times you leave, you will always come crawling back" with a big shit eating grin. Jun rapes his sister while spouting nonsense like "Don't worry Kaname. We've always been together. You don't have to leave me. I'll make sure we stay together forever as brothers and sister. HAHAHHAHA." (you know how this author likes to use Karmic parallels. And Kaname gets raped because she is a girl). Uruma arrives too late: Jun is gone and Kaname is limp and sobbing "Uruma, this time you can't overwrite these memories (in reference to their first time)". SLAAASH. Kaname kills herself before Uruma can stop her. "I'll kill you Jun. I'll kill you Kyou". End of Volume.
Remember... we never saw what really happened in the gymnasium at the end.... after Kyou and friends shadow walked out of the gymnasium like your typical action bad guys. Jun was still tied to the chair, and Kaname's body was on the trolly. And the golden rule is: it's not over yet when people die/disappear offscreen.