It seems odd injecting the potion wasn't even brought up as an option, leading me to wonder; Do Syringes even EXIST in this world, I could see that being what Rudy ends up designing if not.
I hope I'm wrong but Miku's expression and somewhat lackluster grip on Kyoukos waist makes me think she's going...
"Oh no, I'm actually not gay!" Or "That was just a prank,bro!"