Responses
I honestly don't understand why so many claim this chapter to be ''really sad''. As you said, I think the look on Ryou's face on the last page means he's contemplating the possibility of a relationship with Hayato. Also, pining for someone only to discover they had feelings for you all along and then starting a relationship is a common trope in yaoi. That would mean 80% of yaoi mangas are sad.
Even though we all know it's gonna turn happy, we still feel bad for them here in this moment, so that's why it's "sad"
A lot of comments here are about how sad this chapter is, but I think Ryou's loud heartbeats and blushing are a good sign.
I believe he's already imagining what it would be like to be with Hayato, which is why he's so flustered.
Consequently, I'm hoping that very soon Masato and Ken-ni will go away with Take on some photo shoot or something, which will leave Hayato and Ryou alone to sort out their feelings. At which point I also hope our patience will be rewarded with a super explicit and extra long love scene between the two step brothers.