This NPC can be found near Arowe in the Diamond Boss zone in the Kingdom of Rose, as well as inside one of the house ruins at the Forest Pirates in the Floating Turtle.
If the player interacts with this NPC, it will say:
"WOOF WOOF. YO BRO, wanna buy a physical Rocket fruit for 97 Robux? You can trade it to that noob Scientist for a Special Microchip."
If the player says "Sure" the NPC will say:
"Ayt."
The Rocket fruit can be used to complete Cyborg V3 Quests, or traded for a special Microchip in raids.
When the player interacts with him the first time, even if they don't buy Rocket he will give the Title, "The Dog".
It is not recommended to buy Rocket from the Dog House for 
97, as it can easily be bought for 
5,000 for the same fruit, or 50 for permanent Rocket. Rocket is also considerably weak compared to other fruits which can be bought with similar amounts of Robux or Money.