I read that the manga sold 380,000 copies in three volumes which sounds quite good for a seinen and adaptation. Also, the novels are even more violent than the tv series. There is also a CD drama and judging by the cover it's a prequel set around the time Kogami was an Inspector alongside Sasayama just like the novel. But still no news about the second season or movie? Nevertheless, happy new year and may the hyper oats be with you!