To millions of Guns N' Roses fans, the idea of Axl Rose reuniting with the group's classic lineup seemed all but impossible for decades. But Rose's friend Sebastian Bach says he always knew there was a possibility.

Admitting he was still surprised when word got out that GNR would be touring with former members Slash and Duff McKagan this year, Bach told Billboard that he and Rose had a number of conversations about the prospect of a reunion over the years — and although he always shrugged off the notion in public, he offered Bach a somewhat different perspective.

"I always thought that if you can go through my interviews and bulls---, all of the animosity from Axl toward Slash or anybody else in Guns N’ Roses, he would hang out and we would drink a lot of booze and talk about bulls---, this and that," said Bach. "But at the end of every single night going into the early morning or late afternoon, he would always say, 'But Bas, never say never.' He would always end the night with a 'but you never can tell, you know, maybe someday.' One part of me was surprised and the other part was not surprised."

Bach also promised that his upcoming memoir, 18 and Life on Skid Row, will be well worth the wait for fans who've waited years for an official in-depth account of the group's early years.

"I have all those archives. I went through them all and there’s just so much in this book because this is the very, very first-ever Skid Row book," said Bach. "I know in the future there will be more books on the band Skid Row, but when I go to Barnes & Noble, there’s zero. There’s none. And every other band has a hundred books: Motley Crue, Cinderella, Bon Jovi, Aerosmith; every band has 10, 15 books. There’s none on Skid Row. So this is the first one, so I’m going to pack it full of as much info as I can because you only get one chance to make a first impression."

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