Key Financial Data Of Group
| Concept | 2023-06-01 to 2024-02-29 | As at 2024-02-29 | 2023-12-01 to 2024-02-29 | As at 2023-05-31 | 2022-06-01 to 2023-05-31 | As at 2023-02-28 | 2022-12-01 to 2023-02-28 | 2022-06-01 to 2023-02-28 | 
|---|---|---|---|---|---|---|---|---|
| Key financial data of group | ||||||||
| Business results of group | ||||||||
| Net sales | 
                                                333,954,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                454,515,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                340,025,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Ordinary profit (loss) | 
                                                -38,045,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -78,400,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -45,842,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Profit (loss) attributable to owners of parent | 
                                                -33,126,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -89,036,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -51,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Comprehensive income | 
                                                -25,583,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -70,168,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -39,675,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | — | 
                                                546,345,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                571,928,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                602,422,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Total assets | — | 
                                                968,263,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                993,956,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,104,511,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Basic earnings (loss) per share | 
                                                -4.42
                                                
                                             | — | 
                                                -2.27
                                                
                                             | — | 
                                                -11.87
                                                
                                             | — | 
                                                -1.16
                                                
                                             | 
                                                -6.80
                                                
                                             | 
| Diluted earnings per share |  | — | — | — |  | — | — |  | 
| Equity-to-asset ratio | — | 
                                                0.564
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.575
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | 
                                                0.545
                                                
                                                    
                                                        xbrli:pure
                                                    
                                                
                                             | — | — |