I hate this theory, it doesn't make sense because the person who saved Josuke doesn't have a cutout on his jacket and a zippers on his T-shirt. : r/ShitPostCrusaders
Josuke Higashikata Costume Bomber Jacket - JJBA Store
Josuke Higashikata Cosplay JoJo Bizarre Adventure: Diamond Is Unbreakable Coat Outfit Adult Men Women Halloween Carnival|Anime Costumes| - AliExpress
Fanart] I made a Josuke jacket! Based on the OST art. : r/StardustCrusaders
Jacket - Jojo no Kimyou na Bouken / Higashikata Josuke Size-M (TVアニメ「ジョジョの奇妙な冒険 ダイヤモンドは砕けない」 ジャケット【再販】 東方仗助M) | Japanese Official Merchandise - Goods Republic