What's the bet the boyfriend went to meet Misono for the fireworks and saw the kiss?
Nah. They're in a private building. And he already met them earlier. Wait, did you read the chapter? It's all in there.
"It'll end when she fall in love with him"
Thank fucks, this is a yuri manga so it won't end that badly. How many times (in various media) it ended with the straight girl saying she has a "happy and perfect" relationship with the bf now and basically throws the lesbian away without looking back. And then the poor gay girl getting her "happy end" by partnering up with some random guy.