I'm not suree if I remember it correctly, but he said that they are not a yakuza, but his parents own a construction company thats why they are rich haru
Yeah but other mangas have taught me that that's usually the business Yakuzas use for a legitimate front and/or once they go "legit". Buying land and building contracts etc, great way to launder money etc ╮( ̄▽ ̄)╭
https://www.mangago.zone/read-manga/kiraide_isasete_asanaga_sensei_to_yanagi_sensei/uu/to_v-2-chapter-3/pg-19/
Also, i completely forgot Asanaga sensei was from a Yakuza family