In Japan there is a strange culture of collecting stag beetles in the wild and keep them as pets. The Japanese call them "Kuagata Mushi". There is an entire industry behind this serious hobby. Shops sell portable cages, nets, food, soil, wood, leaves, and even cleaning sets consisting of brushes and tweezers. This speciman here, I found in Hokkaido. It's a female recognisable from its missing antlers.