Attempting to summon a creature without a Contract is literally gambling with your soul. However, Uzumaki Naruto is extremely lucky when it comes to gambling and manages to summon something that won't kill him outright.

"Sur-PRISE!"
"Gah!"
"Hi! I'm Pinkie Pie."
"Uh... I'm Uzumaki Naruto, future Hokage!"

Reading an epic tale of one of the Third Hokage's missions, a 6 year old Naruto sets himself on getting some awesome summons of his own. Unable to find a contract on short notice, and not understanding why a contract is required, he goes through the necessary motions anyways and winds up in Equestria. Can Naruto convince the locals to let him be their summoner? Is the ninja world ready for the likes of Pinky Pie? Just how much will a young Naruto benefit from the Magic of Friendship?