UUID: 300035323209471

Server ID: S909

In-game Name: UchihaFookU

Answer: in the woods of Konoha, Naruto spells out "I LOVE YOU, HINATA" with the kage bunshin no jutsu technique in the Konoha Woods where they first met, when Naruto tried to protect Hinata from the bullies and ended up getting beaten up - the consequence of which was Hinata falling in love with Naruto for the very first time.