Everyone is like "Hotaru should just confess".
It would be a stupid move at the moment. As long as Yuma has not accepted her own attraction to Hotaru, any confession is gonna be rejected as "we are both girls/I have a boyfriend".
In that relationship, there's no need for a confession. Acts speak louder than words.
I don't know why none mentionned the most realistic scenario, that often happens in real life : Yuma cheats on her boyfriend AND STAYS IN A RELATIONSHIP WITH HIM, while hiding her betrayal. It looks like she's taking that route. The feelings don't even have to be voiced or acknowledged.
That she'd be confronted about it, either because she's walked in on, or because Fujiwara breaks the news to Takeda is entirely another issue.