Kazuya was mistreated by his boss, and he was both physically and mentally exhausted. The only one who still helped him was his senpai at the workplace, Miori. He can keep going on because of her support. However before long, he quit the job upon her recommendation.

“It’s fine not to give it your all.”

With those words, it seemed like all the stress disappeared and he could just enjoy a simple life where she would take care of him all day long.
Source: Hau~ Omochikaeri~!