Turns out the one spreading the rumors was Hashimoto, who did so at the behest of Sakayanagi. Shortly thereafter, Sakayanagi appears before Class C and she informs them she has evidence regarding the rumors about Ichinose.
Will you come to the very end with me?
هلّا أتيتم إلى النهاية معي؟
rimaneste con me fino alla fine.
Vocês irão até o fim comigo?
теперь, когда знаете правду?!