Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - JPY (¥) ¥ in Thousands	Mar. 31, 2025	Sep. 30, 2024
Schedule of Property and Equipment, Net [Line Items]
Total property and equipment, gross	¥ 685	¥ 685
Less: Accumulated depreciation	(422)	(324)
Total property and equipment, net	263	361
Computers [Member]
Schedule of Property and Equipment, Net [Line Items]
Total property and equipment, gross	366	366
Furniture and fixtures [Member]
Schedule of Property and Equipment, Net [Line Items]
Total property and equipment, gross	¥ 319	¥ 319

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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