Talk:Saigo no Uta (サイゴノウタ)/@comment-32371753-20170623190844/@comment-2602:306:3419:E190:1CA:92D3:8F39:864D-20170819081248

Figured it out, before triggering the endings as Ciste go to the nexus. Go the the top left corner, take one step down, and press Z. You'll be able to enter the code then for a nice little easter egg/cheat.