I kinda love this anime for some reasons, but it's a guilty kinda love.
Who never wished they could just enter a relationship with the prettiest person in class, without even putting on any effort?
While it's a dream for many, it's also a bad sign for this story. This is not really how normal people work. Runa is kinda insane for accepting this and bringing his new boyfriend to bed RIGHT AFTER they start dating.
Some anime try to make us feel sorry for the so called "slutty misunderstood girls". They are just victims after all, right? They want real love, but the only people they find are jerks who have sex with them and abandon them right after.
Well, maybe don't just accept anyone who confesses to you? Maybe have some freaking criteria? Runa keeps making the same mistake over and over again, and for some reason doesn't ever think to change her strategy.
Ryuto is kind of a coward, as he admits. He doesn't accept Runa's advances because he wants to do it only when she "actually" wants to. That's a good feeling, I must say, and it's a far better excuse to avoid sex in the story for quite some time. However, his personality can make you annoyed quite easily too. He seems incapable of telling his girlfriend how he is feeling and what is going on. The lack of talk is precisely what creates so many stupid dramas.
I know lack of communication is realistic an all. But still, realistic doesn't mean interesting. I don't want to spend episode over episode getting frustrated over something that could easily be solver by a single honest conversation.
Runa trying to break up with him is just the worst. And she does it for pretty much no reason. It's like she thinks Maria and Ryuto are a good match, and... That's all? I don't think she understands it either. Why would you throw away a good relationship (at least compared to the previous ones) for such a lame excuse?
Aside from that, there's the "intense stare girl" assaulting people, there's the hypocrite pop fan rejecting the fat boy and then getting in love with him after he loses weight... So many VERY flawed people.
And that's usually a good things. Characters should be flawed. They should have problems to deal with.
But it feels like they never properly address those flaws. They just move along with them.

The only thing that really evolved was Maria. She came to school trying to make her sister happy, got upset that Runa didn't talk to her, tried to steal her boyfriend and finally made peace with her. Still, it's hilarious how this girl causes nothing but trouble the entire anime, even when she doesn't want to. A fucking SEXUAL PREDATOR comes out of nowhere just so Ryuto has to help her, and it creates a misunderstanding with Runa. At this point why not make an evil unicorn appear and impose rules on Maria and Ryuto "you must kiss every day, and you must not tell Runa why, else she will die"?

I must say the show can hit really close to home sometimes, but I would still prefer if there was less focus on overcoming drama and more focus on developing their relationship.