it's fine i hated raika too bc i shipped (and still ship) garo and totonou, so you're not alone in hating raika…
Even if I ship him with Furomitsu, I have to admit that he has developed more feelings for Garo (aparently) than for her. And that hurts, but i´m still hoping for my ship. Also Raika was all of suden, I can´t stand her and her mystery vibe.
About romance you said exactly what is on my mind. There was not love, like we don´t know, no one does, not even him.
And also to add that this drama is based in a real story (Since I don´t know what the real story was, I don´t know if this drama was really accurate).
For me it was good. The acting, ost, and the story in general because is based in a real story. That doesnt mind I´m ok with everything that happend there, because it broked my litter heart. I was literally expecting her to be happy with him at some point and that never happend. I really enjoyed the drama but the last five episodes where so... I think the drama is whorthy to watch but not if your looking for romance.
But I can understand totally why you feel like that.
K-Drama 
And also to add that this drama is based in a real story (Since I don´t know what the real story was, I don´t know if this drama was really accurate).
For me it was good. The acting, ost, and the story in general because is based in a real story. That doesnt mind I´m ok with everything that happend there, because it broked my litter heart. I was literally expecting her to be happy with him at some point and that never happend. I really enjoyed the drama but the last five episodes where so... I think the drama is whorthy to watch but not if your looking for romance.
But I can understand totally why you feel like that.