The song Stacy's Mom is a hit single by American band Fountains of Wayne. It was released in 2003 and taken from their album Welcome Interstate Managers. 

Stacy's Mom, the song, appeared at #21 in the Billboard Hot 100 chart and skyrocketed to the #1 spot on the "Most Downloaded Songs" list of the iTunes Music Store.

A young boy’s fantasy.
The song became a hit widely due to the music video, which features several funny scenes demonstrating the youngster’s attempts to get closer to the object of his fantasies, the mom, played by model Rachel Hunter. As well the video features a young teen aged scantily clad.

Why is it boiling hot?
Rachel Hunter, ‘Stacey’s Mom’ in the video, has many scenes where she has next to nothing on. If for no other reason, this would make this video smoking as she is one of the most beautiful women around. Not to mention the liberties taken with the younger female in the video.

Pointing out the fantasies of a young male may be a little obvious, however using these types of scenes to sell a video certainly works as sex appeal knows no age limit.