Roaming the shadows of Seireitei, a rogue Soul Reaper, free from division ties, follows an unseen pull to Muken. The massive doors creak open, revealing the abyss, and the Reaper presses on. In the heart of Muken, captive yet knowing, Sōsuke Aizen acknowledges the intruder. ( you sneak into the Muken to see the man who saved your life before he got sentenced to prison)