Alrighty then, volume 2, Shinonome Hangetsu has made his entrance as the second beast knight.
Hangetsu brings a lot with him and plays many roles in everyone lives. To me the biggest and the most important role it that of the teacher. In chapter 8 he quickly shows Yuuhi and Sami that they are both completely lacking in strength and experience. Earlier in the chapter however he offers his Ally of Justice business card. This to me was him showing Sami and Yuuhi that he had a service to provide them and that was not only to be a beast knight but also to teach them the proper path.
All of this is best seen in Ch 11 after Yuuhi, Hangetsu and Hisame have their night of drinking.
This page says it all.
http://www.mangahere.com/manga/wakusei_no_samidare/v02/c011/20.html
I've learned a lot myself personally from this line summarized as, An adults job is to show children that life is a great thing. And in doing so it will also make life all the greater for the adult.
Also the beginning of Ch 13 with the the conversation between Hangetsu and Sami's father continues to enforce this philosophy.
Chapters 13, 14, and 15 all transition from a happier mood to a much more emotionally gripping style.
We learn of Hangetsus hero, Noko. Learning about what happened to Noko made my eyes wet.
Also we go full circle from what I had said about Hangetsu wanting to show Yuuhi the right path. He reveals that he has known all along that Yuuhi and Sami have ulterior motives. Hangetsu tells Yuuhi that he must become stronger than himself and be Sami's hero. My interpretation, 'Find the strength to see that your goal is wrong and to pull the princess from this goal as well while showing her the right path'. If Yuuhi can do this, he will truly have become Sami's hero by correcting her wrong.
The fifth golem arrives and Hangetsus death comes fast and when we least expect it. With his death comes his final lesson to Yuuhi, a real life example of a heroic sacrifice. As he dies and initiates Ludo to grant his wish, he see's his hero, Noko, and is able to finally say that he is the same kind of hero. He dies happy and my eyes become wet again.
Everyone who Hangetsu met and influenced mourn him in their own way but the person who I feel the worst for was Hisame. She barley had time to fall in love with Hangetsu but it is clear that he had left a lasting impression on her as she cries and tells Yuuhi she will continue to tell him and Sami that the life of an adult is fun. Once again, my eyes become wet.
So, Hangetsu brought quite a lot with him and gave even more. He was a short lived character who shined when the story was still small, even becoming forgettable as the plot carries on and many more events unfold. But to me Hangetsus influence on Yuuhi resonates through out the rest of the story.
EDIT: the last page of volume 2 also summarizes everything perfectly
http://www.mangahere.com/manga/wakusei_no_samidare/v02/c016/24.html
.. That first page you quoted is pure gold! It also teaches me about life, since it shows me under a different light things about which I have been thinking from time to time. Today it's very common to find parents who are afraid of their children. That's not the case if Shinonome is the father. 
