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Heart Dimension (心次元, Kokoro jigen) is one of the 3 dimensions featured in Megadimension Neptunia VII.
This dimension has the strange ability to turn dreams into reality.
This dimension largely consists of empty purplish colored space except few destroyed ruins and a giant Share Crystal within the center.
Megadimension Neptunia VII
Heart Dimension along with Zero Dimension serving as its entrance was the result of Uzume Tennouboshi's dream while being sealed in the Swirl Console. After some time, she fell into the whirlpool of delusion, losing Share Energy as the source of her power and gaining Negative Energy as a substitute, she desired to escape her seal.
She attempted to destroy the Zero Dimension to get into the Hyper Dimension. To do so, she created the Dark CPUs. This caused her soul to split and fight the Dark CPUs in the Zero Dimension. During which, Uzume used Heart Dimension as her base. Her plan to destroy the Zero Dimension yielded no results.
Some time later, Neptune and Croire landed on her dimension, as an emergency stop as Croire was running low on energy and the two did not want to be stopped in between dimensions. However in actuality, Croire notices that something has happened in this dimension and thinks she can use this as an opportunity to get out of her prison.
Uzume sees the pair and explains to Neptune that she is bored and would like her to get the Swirl Console in Planeptune's Basilicom in the Hyper Dimension. She entices Neptune with the offer that they would play together on the console. Neptune tells Croire to set the warp co-ordinates and the pair warp away. With that, all events are set in place for the story of Megadimension Neptunia VII to occur.