Kiriyama revealed that when he first got the offer to appear in "Kizoku Tantei", he actually thought that this would be his first appearance in a Getsuku drama. Back then when he appeared in "Nodame Cantabile", he only had one line but fumbled through it and ended up being scolded so he didn't quite remember what happened there because he was too nervous. As it had been more than 10 years since then, he is filled with deep emotion about being able to appear in another Getsuku drama again. When asked to comment on his character, Kiriyama described Hiroki as someone who isn't a kind soul and uses his wealth and status to have his way so it's quite exciting and enjoyable to play a person like this.
Sources: Sponichi / Oricon