Honestly this chapter makes me the most confused. If Kaizaki said "I quit because I was emotionally scarred after walking in on a coworker who had committed suicide" that would be completely understandable. I get he was originally stressed by the company life, but his social skills are better...
@watercell you’re probably right, but
SPOILER
The fact that Natsuki left the letter when the maid visited means that the maid is it but it’s really bad or that it’s not the maid but rather a servant for Natsuki.