Emblem3 are paying tribute to their late friend Christina Grimmie, who they say had planned to tour with them prior to her tragic death.
Christina and the guys of Emblem3 each found fame on reality TV -- she on The Voice, they on X Factor -- and had previously hit the road together on Selena Gomez's Stars Dance tour in 2013. Emblem3 is currently in the midst of their Waking Up tour, promoting a new EP of the same name.
WATCH: Emblem3 Debuts New 'End of the Summer' Music Video
Keaton Stromberg told ET on Friday that the trio last saw their late friend about "a month or two ago," while Wesley Stromberg chimes in that they had been "just texting the other day talking about doing YouTube videos!"
"We still can't believe this happened," he added solemnly.
Christina was shot and killed on June 10 as she signed autographs for fans following a performance with Before You Exit in Orlando, Florida.
"We were in Orlando three or four days before all of this happened. It just, it hits home because we're in the same world, we're out there touring, playing these same venues, similar venues, and you never know what kind of people are in the audience," Keaton said.
"Both of them [Christina and Before You Exit] were supposed to open for us on this tour," added Drew Chadwick. "So, we had this more direct personal thing with them 'cause we're like, wait, that would have happened at our gig. But even more than that, it's like, we knew Christina and she hung out with us a lot."
PICS: Inside Christina Grimmie's Final Performance
Keaton remembers her as "amazing" and "one of the nicest people I ever met," while Wesley said she was "one of the sweetest souls."
"Do I mourn for a really long time? 'Cause I could easily just freak out about it, or do I just keep living my life?" he mused.
"It's one of those things that's so surreal, you almost don't really know how to react," Drew confessed. "You sit there kinda dumbfounded."
As the band continues to tour, they plan to beef up security but won't cancel meet and greets with their loyal fans.
"We just wanna make sure that everyone's safe," Keaton explained. "This tour we actually didn't end up bringing security out because we had a lot in the past, and we've kinda grown up a bit. But we just realized that there is a boundary between some people."
A memorial is being held for Christina on Friday in New Jersey. As ET previously reported, Adam Levine, who coached Christina on The Voice, is paying for the funeral.
WATCH: Selena Gomez Breaks Down During Tribute to Christina Grimmie