I supposed to read it first to make it clear about yumi and kan-chan's story. But this is the series i read last , when this story is too beautiful. But still understand the plot. I love how tanaka sensei arrange the story in different post. Whatever you read the series isn't in the order, you will always understand the story.
I dont like threesome, but it is exception i hope he ended with tomoya, because i think he is going to help escape from that beast.