The Crystal Kingdom of Chalcedonia was once a beautiful place, under the rule of Princess Rosalia, they lived happy peaceful lives. Until one day, monsters called Nightmares destroyed the kingdom. Princess Rosalia and her fairy knight Diana hid deep in the castle, praying that their last hope, the magical Rose Crystal Mirror would produce a miracle, and save their home, however, they were attacked by the leader of the Nightmare Agency, Druzy. Diana fought helplessly before finding herself transported to Earth, but her Princess was nowhere to be seen.

Unfortunately, the nightmares began to attack this new world too. Valerie Amaranth, an ordinary 16-year-old, has her world changed forever when she receives the powers of the Legendary Crystal Warrior Diamond Heart. Now with the help of Diana, she must find her allies, defeat the Nightmares, and rescue the missing princess Rosalia.

Will Val defeat the Nightmares, make new friends, and find the love of her life along the way? Or will she meet her tragic end? Your choices decide her fate and the fate of humanity in this magical visual novel!

Magical Warrior Diamond Heart is made to be played multiple times. This visual novel has multiple endings and scene variations depending on your relationship with the cast, and characters will react to and remember previous choices you've made. Characters may even react differently depending on how the player chooses to interact with others, meaning tons of content to explore!