Well done, Ishigami-kun.
I hope ppl won't hate her because she was honest about her feelings. She really does care about him, but she doesn't have romantic feelings for him. There's nothing wrong with that, it is what it is. She would have been worse to lie about her feelings and lead Ishigami along. I respect people who are honest when it comes to this stuff.
I love that Aka made it clear that it's hard to be friends after rejection. Not wanting to be friends or being unable to maintain a connection after rejection is normal because it's a painful event. Not being wanted by someone you are in love with hurts, so of course, anyone will want to distance themselves from a source of emotional pain.
Even if Ishigami cannot keep his end of the bargain and eventually distances himself from her, he will not be wrong, and she will have to respect his decision to not maintain a friendship. She knows what she asked of him is unfair.
Either way, Ishigami behaved exactly the way you would expect him too. He's a good guy. He doesn't realize that there is someone that feels romantic love for him, I hope she will let her feelings be heard.