Mister Plum

Dave picks up coffee every morning at the train station on his way to work. He can't help but notice when the man in front of him is given a plum-colored cup holder, as it goes perfectly with his own tie. There are other things he can't help but notice, like how hot "Mr. Plum" is. When Mr. Plum hands over a cup of coffee, exactly how Dave likes it, the morning he's late getting to the station, it's the start of a beautiful friendship. Or is it?