"Two or more people saying the same thing."
Explanation here,
http://www.talktomeinkorean.com/shows/ctw0510/
It's not about lips getting together and kissing, which could be misinterpreted as... Haha
2015년 1월 19일
3
1
0
Sorry..'about' should be changed into 'that'.
2015년 1월 19일
0
0
0
Here ~라고 입을 모이다 means to have the same discussion about~.