I'm trying to remember the name of this yaoi I read over a year ago where one of the characters delivers flowers to this company (he has long hair in a ponytail I think?) and the other sleeps around with his boss/employer while at work. Any ideas?

https://www.mangaupdates.com/series.html?id=48643

I believe the story that you are looking for is called Kawaisa Amatte Nanika ga Hyakubai.