Junna, the protagonist of a game developed by Princess Soft, has a sibling named Senna. He attends an esteemed school as an ordinary student, but his life took a tragic turn when a car accident claimed the lives of their parents and wiped his memories from before the incident. Since then, Junna has resided solely with his twin, albeit with the assistance of his relatives. In the present day, the siblings attend the same high school, and Junna finds solace in the fact that his experiences are shared with Senna. The prospect of beginning anew in a different setting and meeting new people lifts his spirits, allowing him to momentarily forget his painful past. However, as time passes, his recollections of the accident resurface, leaving him conflicted about his current situation, as well as his future. Despite the happy days he cherishes, the question of what really transpired on that fateful day haunts him relentlessly, making him ponder what truly lies deep within his memory.