I didn't expect much from this. I wasn't convinced by the plot, but still decided to give it a chance and it didn't disappoint me.

I don't think I can say anything bad about this. The only reason I'm not giving it top scores is that the story was really nice, but not so much as to deserve a higher score.
That said, everything else was perfect. The ending was a little bit disappointing, but not bad. I just expected a little bit more. I loved all the plot twists this has. They never give you any hint as to how the story might develop, it feels like a puzzle game were you need to wait for every piece to come together to understand how things really are.
The concept of the voice in the rain is weird, but at the end of the day is not as important as it may sound at first. It's really about love being the most powerful energy that can make two people get close or push them away. It's all up to how the characters behave.
I also appreciated how the show dared to talk about some controversial topics.

It's a really good show I highly recommend. Might not be the best out there, but it's still enjoyable.