Mai had never been into an apartment building but she often imagined living in it. It just seems fun when you see it from Korean films or dramas. The building is high and luxurious, Mai was amazed when she entered it, the guard was also quite strict. Each occupant has a key that must be attached to a sensor located at the entrance. The elevator to the top was behind that door so it was clear that outsiders couldn't enter carelessly. They must first ask permission from the security guard and they must first be asked what their business is. Of course, the people who live here must be people with money, the price of one unit must be very expensive.