18+ Tsuki no Joou no Nekashitsukekata

Rookie editor Yaichirou Hitsujiya's overly gentle nature is a double-edged sword, causing his assigned authors to avoid meetings because they find him too soporific. He desperately wants to help these authors, but...! So troubled, he is delegated the task of delivering materials to the popular author Sumika Tsukishiro. Tsukishiro is known for her extremely difficult personality, but that day, sleep deprivation has made her childlike. Determined to get Tsukishiro to write her novel, Hitsujiya resolves to lull her to sleep!

(Source: Kodansha, translated)