This volume was chalk full of plot in various ways, and we love to see it. There seem to be three major threads at work in the series right now. One, being Taichi looking for a new job, and while he finally gets an offer, and the majority of his superiors in the interview liked him a lot, who I'm assuming will be his new boss, gave him a failing grade. So, there will be some problems with that going forward.
Second, is the new hire, Sudo, at Kohei's workplace. I honestly don't remember what he did before he was hired, but this kid has a chip on his shoulder you can see from a mile away. He's judgmental, is unable to admit his mistakes and is constantly trying to one up other people, to say nothing for how little he thinks of Kohei. In an attempt to get dirt on Kohei for any future problems he manages to get a picture of Kohei and Taichi kissing. He hasn't done anything with the photo yet, but I bet that will be one hell of a bomb when it goes off.
Third, and the most heartbreaking, is that Kohei's father has decided to finally get back in touch with him after around a decade of neither seeing or speaking to his son. So far we've only had hints as to why Kohei went to live with his grandparents in the first place. His grandfather is the only one still alive, but they do not speak about Kohei's parents at all. While it seems as if his father wants to get back in touch, Kohei is once again let down by his dad, much to Taichi's horror, when he figures out why this is the reason why Kohei is the way he is. Always being aware of everyone else's feelings, but has little regard for his own. Based upon a flashback we get at the end of this volume from before Kohei went to live with his grandparents, it looks like his father has always worked far too much, which gave him little time for his family. Somewhere between that point, and Kohei living with his grandparents, Kohei's mother either takes off, or dies, and his father, unable to take care of him on his own, leaves him with his parents, effectively abandoning him. It's a rough backstory to have, and all of these threads will likely made the next volumes gut wrenching at some points, but I am definitely looking forward to where this story goes from here.