The Bulgaria Under-21 star completed his move to the Old Lady on Friday.
“I met Gigi Buffon and I’m happy,” Kirev told journalists. “I am enthusiastic and proud to have become a Juventus player.
“I have got to know Juve and I like the club a lot – this has been a really emotional experience.
“It’s fine that I will be sent to Grasshoppers and I will show my value there before I return.”