The strong ties between groups 2AM, 2PM and the Wonder Girls were once again revealed.

First, Wonder Girls’ Ye Eun posted on her Twitter on March 12, “2AM’s ‘I Wonder If You Hurt Like Me is daebak!” Then 2AM’s Changmin responded to her with a, “Thank You.”

Following that, 2PM’s Junho posted, “2AM’s new album is out now. Please give lots of love to ‘I Wonder If You Hurt like Me.’ Changmin hyung, Chamkwonee, Seullungee, Jinwoonie, (nicknames for Jo Kwon, Seulong and Jinwoon) fighting!”

2AM released their new mini-alum, “Fitzgerald’s Way Of Love,” on March 12. Moments after the release, their title track, “I Wonder If You Hurt Like Me,” reached the number one spot in various music sites, achieving an “all-kill” status.

Netizens who saw these interactions commented, “What a strong friendship,” “Brother groups 2AM and 2PM, I hope you guys will be forever,” “‘I Wonder If You Hurt Like Me’ is so daebak,” and many other positive words.

Meanwhile, 2AM will make their official comeback through a showcase that will be posted on YouTube on March 13.