So impressed or stunned that you have the feeling of being surprised pleasantly, like when you listen to an amazing band for the first time.

The name comes from the movie and comic book series Scott Pilgrim. Sex Bob-Ombs is the name of Scott's band, and Knives (Scott's ex) was utterly impressed with Sex Bob-Ombs, and fell in love with the band immediatly. Thus, the Sex Bob-Omb effect kicked in, leaving her stunned.
Person 1: Have you listened to the new song by Crash and the Boys?

Person 2: Eh, it was okay, but didn't have a Sex Bob-Omb effect.

Person 1: What do you think of this music video?

Person 2: *unable to speak from the Sex Bob-Omb Effect*
by Jennifer the Dark May 29, 2011
Get the Sex Bob-Omb Effect mug.