Kono Otoko wa Jinsei Saidai no Ayamachi desu

Following the death of her pet dog that had accompanied her throughout high school, college, and even as she entered employment, Yui Satou was drowning away her sorrows at a bar when the man beside her shares what he thinks of her sorrows. He tells her to either overdose to meet her dearly departed dog, or take something for her "dull-looking head" and wait her turn to die. Having earned her malice, Yui trips him up as he goes to leave. While thinking to herself the next day that she might have overdid it, the man from the bar comes looking for her... and it just so happens that he's the CEO of the company she's employed under?

(Source: Solmare Henshuubu, translated)