HaruChika author Hatsuno Sei was interviewed in September 2015 for University Co-Op’s Dokusho no Izumi column. University Co-Op released the first two sections on the website with the remainder published in their magazine. The interview contains some spoilers for stories occurring after the HaruChika anime. The first section in particular has talk about the most recently published book “Planet Charon”. If you prefer less spoilers you could skip “1. HaruChika’s New Work” and move on to the second part.