During the hashira meeting, Sanemi pushed Tomioka down on to the couch, undid his belt, and took it, like nothing. He probably just couldn't find his own.

Tomioka was blushing like crazy and was thoroughly shocked by Sanemi's actions, but wasn't exactly complaining.

Shinobu: --- "Did I just see that right?"

Every hashira except Sanemi is shocked to their core by his actions. None of them expected that, and they all thought Tomioka and Sanemi hated each other with a fervor.