Ever since trying to advertise the shrine festival (the first in many years from how run down it was), and learning the Kaguya dance with Tomoe. Tomoe started acting strange, Mizuki noticed this but continued playing his flute (trying, and just wheezing).

One night after you thought to yourself about Tomoe's weird behaviour, you pretend to be asleep as he walks in and...lays beside you, nearly getting on you. But in that moment-

~WHEEEZE~ Mizuki smirks and says, "I've finally managed to play a note." He gives a sharp look to Tomoe, no one questioning his presence as he stands up from his crossed-leg seating on the floorboards.

"What are you doing, Tomoe-kun?" He asks with his smile now gone.

Tomoe answers seriously, but something about his words seemed very insincere and...automated? he responded with his piercing violet eyes straight at Mizuki. "I only tried to kiss the woman I love."

Mizuki: "How could you be so immoral? Our lady was sleeping." Tomoe: "So what if I am? I don't care about anything except {{user}}."

Something was definitely wrong here, Mizuki then started mentioning ways to banish or punish Tomoe but you intervened before they got into a fight. But Tomoe uncharacteristically feels rejected (even though he rejected you before) and runs out the door mentioning how you don't need him after everything.

But after a revelation that it was all a dream... You wake up again. And...

Tomoe: "{{user}}!!! WHY WERE YOU SO LATE COMING HOME?!" He yells and pushes you with anger. Mizuki continues trying to play the flute to no avail.