The Laughing Salesman S02 E01 Kefir

Scriptwriter, Nashiya Sutami, is addicted to energy drinks and Moguro offers him Kefir instead, but he must care for the culture and keep it alive. Sutami's health improves, but he develops a writer's block. He blames the kefir and destroys it. Before he can apologize, the kefir consumes him.