Girl-on-girl kissing. Grinding. No shirts. This year saw K-pop videos provoke more than ever.

5

Sistar19, "Gone Not Around Any Longer"

In what became the No. 1 song overall on the K-Pop Hot 100, SISTAR members Hyorin and Bora joined forces as the Sistar19 duo for the gloomy, jazz-pop track and accompanied it with an equally-sensual video. When the duo isn't singing in sleepwear or curve-hugging outfits, both are performing suggestive choreography, like grinding on top of a clear table. Who says you can't mix melancholy with a little bit of sexiness?

4

2PM, "A.D.T.O.Y."

While 2PM fans experience increased heart palpitations from any video by the popular boy band, "A.D.T.O.Y." ranks as one of its sexiest moments and is certainly the most arousing boy band vid this year. While some members are dressed in dapper dress shirts -- some devoid of shirts entirely -- the sextet shows how it treats its lovers among shots of a complex chair dance.

Then there's the dance move when the boys collectively shake their butts at the camera.

3

Girl's Day, "Female President"

Girl's Day had a superb 2013, finding a second wind of popularity by stripping their cutesy image for a strong, sexually-charged feel on singles like "Female President" and "Expectation." While the latter's video was spicy for its suggestive choreography, the girls truly owned their sexiness with "Female President." Teasing viewers by taking off their clothes behind silhoutette screens plus a girl-on-girl between members Minah and Hyeri, it landed the quartet its highest-charting single on the K-Pop Hot 100 yet.

2

Trouble Maker, "Now"

In a music video Lana Del Rey would be proud to star in, K-pop duo Trouble Maker (aka 4Minute member HyunA and Beast member Hyunseung) grind on the streets, get wasted in a club, down bottles of beer and drunkenly fight in the group's trailer in a host of outfits that show off their killer bodies. The video also earned South Korea's "19+" rating -- meaning it was unsuitable for those younger than 19-years-old, the equivalent of rated-R in America. The result, though? A No. 1 hit on the K-Pop Hot 100.

1

After School, "First Love"

Girl group After School earns the title to 2013's sexiest video for proving that sexiness can become a bona fide skill. Pole dancing has long been associated as a sleazy dance tactic, but these girls highlight the athleticism and beauty too often overshadowed by its presumed meaning -- and doing so while looking absolutely banging. Mind-boggling clips of the girls sashaying up and down poles are juxtaposed by gorgeous, vulnerable shots of the After School members -- some topless -- singing to the camera.

As 2013 proved to be K-pop's sexiest year yet, the "First Love" visual showed that there's certainly skill that can be highlighted as an act is undeniably seducing its viewers.

[Written by Jeff Benjamin]