4ever is a Chinese boy band that came out this year. Looking at the picture, from left to right, the names are Latte, Jolin, Qin Yue, and Dean. Their ep came out on June 10th, 2012.
Here is one of their music videos called Let's Go. Check it out below.-
[官方HQ] 4ever Let's go (MV完整版)-
Picture credit- Facebook.com