I know this guy, let's call him "Mr. X". Mr. X gets off work one Friday, and as he is getting into the elevator, so does one of his female coworkers ("Miss Y"

. Mr. X is kind of surprised, because usually his female coworkers will duck into the nearby ladies' room if they see him getting into into the elevator after the work day has ended.
Anyway, Miss Y, who recently entered the company, gets next to Mr. X in the elevator and strikes up a conversation. There is the usual chit-chat, which, when it does occur, usually ends on the 1st floor where the elevator stops. However, Miss Y continues to walk with Mr. X to the train station, which is extremely unusual. And even when Mr. X stops to buy his ticket, Miss Y stays with him. This usually doesn't happen even when Mr. X is talking to a male coworker after work.
Anyway, they get in the train together. Mr. X is headed for Tokyo Station, Miss Y is going to Akihabara, two stations after that. They continue to talk in the train. For Mr. X, this is the first time in 4 or 5 years that he has talked to a lady in a Tokyo commuter train. The conversation appears to go well.
When the train arrives at Tokyo Station, Miss Y says, "Is this where you're getting off?" Mr. X replies, "Oh, heck, might as well go to Akihabara, because we're having such an interesting conversation."
At the turnstile at Akihabara Station, Miss Y says, "I'm meeting a long-time friend here and we're going to have dinner at a restaurant. Maybe you can join us?" Mr. X is very keen to that idea, so Miss Y goes off into a corner of the station and phones her friend. The restaurant is a reservations-only place, so it takes a while to get everything set up. But eventually, Miss Y comes back and says that it's OK, Mr. X can make it a threesome.
So the friend ("Miss Z"

meets them at the station. They walk together to the restaurant and have a great time. During the conversation at the restaurant, Mr. X finds out that he has several things in common with Miss Y. Miss Z, the longtime friend, turns to Mr. X and says, "Looks like you've got a new girlfriend." Mr. X and Miss Y exchange coy looks.
The conversation continues until the reservation for the table has expired. Miss Y and Miss Z have further plans for the night, while Mr. X has to go back home because he has to work at another job the next day. So they accompany him to the train station. After everyone says what a great time they had, Miss Y tells Mr. X, "Monday, give me your private e-mail address".
Well, Mr. X's heart starts pounding when he hears this. After years of loneliness, and several unsuccessful attempts at dating, it seems like he might be able to finally get into an interesting relationship with a woman. He can hardly wait for Monday.
Monday comes around, and Miss Y seems to ignore him at work. But eventually she comes by Mr. X's desk and talks to him briefly about last Friday's dinner, and Mr. X gives her his private e-mail address, and eagerly awaits for her reply. But she writes a kind of a generic reply, and Mr. X is a little disappointed. But eventually, he sends her a reply telling her how he loved the get-together and how he would love to do it again. Miss Y replies that she would love to do it again as well, but first she wants to make as many new friends at the company as possible. Mr. X scratches his head and thinks, WTF?