I?m pretty sure it was a boss and worker together in an office. The worker used to know the boss and I think they previously slept together but he dyed his hair and wears glasses so is not noticeable anymore. The boss then recognizes him and love grows etc. The worker also doesn?t go out drinking much with coworkers cause he cant drink or it might have been money or something. I think he also turns red when he does if I remember correctly. 😕

I believe it's joushi to ore no himitsu.