Momentum is a bicycle brand owned by the major Japanese distribution group Aeon. The flagship carbon frame model sold by Momentum was the iwantRC. The iwantRC was manufactured as an OEM product for Giant, one of the world's leading bicycle brands, and is a high-performance model that is generously equipped with Giant's superior carbon moulding technology.

Year 2025. The social game "Crown Hearts", which depicts the battle between the kingdom of princes "Stellar Crown" and the kingdom of princesses "Floris Hearts", has become a huge hit, and professional gamers are as popular as professional athletes in the world. The main character, Aiuchi Koharu, is a naive childhood friend and promising new pro-gamer, Mea Nekoyashiki. Her younger sister, Hiyoko Aiuchi, who is kind to everyone and has a bit of a black heart. Together with her friend and very popular internet idol 'Kumano Midou Ayane', she attends the private Luminous Academy, where she spends her days having fun. One day, Toraharu and his friends visit the opening ceremony of Crown Hearts' annual event, the 'Divine Crown War'. However, what was taking place there was the announcement of 'Crown Hearts VR', which uses the latest VR technology to allow players to enjoy real battles in the real world, and the declaration of the 'Divine Crown War VR', the Divine Crown War that will be held using the VR system. Furthermore, it was also rumoured that in the Divine Crown War VR, "if you win, you can make one wish come true for anything". Thus, the battle royale between 16 top players, the 'Divine Crown War VR', began. 'Crown Hearts, get ready! Battle!"

A mysterious girl who led Toraharu (Koharu) to Real Crown Hearts. Originally a navigational character in the game, she stays in the real world and lives with Toraharu and her friends. She claims to have amnesia, but she is also seen to be subtly clunky and buggy. ...but she thinks she is a solid person. Everything she sees in the real world is new to her because she has been repeating the same things every day in the game world. She has an insatiable appetite, especially as she has never known what it is like to eat.