Oh wow. So we have Sakura getting advice from her co-workers and using it as a way to encourage Shinobou to stay motivated... ( She's trying very hard to make him happy ). However, it's not what he wants to hear. Meanwhile Fumi's true feelings sound very supportive of what Shinobous doing instead... Then he has a flash back of what Fumi said? Oh yeah, I think MC is gonna be the one to NTR this time... They are definitely about to break up, then Sakura is gonna get railed by the other actor, Fumi will become the new GF.
Another route is Shinobou being too busy, and telling Sakura he's too tired for sex, making her feel unwanted... She'll try to understand it bc he's trying to produce a movie, then all of the noise in her head that her coworkers are telling her push her to new management, they break up, and she screws the handsome guy