Sachiiro no One Room Gaiden - Seikai no Meitantei

This is the story of Detective Matsubase three years before he fatefully meets xxx. Hijiri Matsubase finally quits the police force and fulfills his dream of running his own detective agency. However, life isn't smooth sailing as it seems and the poor guy is in massive debt after getting scammed. Luckily, or unluckily for Matsubase… Aketoyo, the son of a billionaire reaches out to him for a deal. "Entertain me, I'll pay you $100,000 per case." A deal with the devil can be oh so enticing. (source: AOC Translations)

17 chapters

• Chapter 14.5 — Yashiro Diary 5
• Chapter 14 — Commission 14
• Chapter 13 — Commission 13
• Chapter 12 — Commission 12
• Chapter 11 — Commission 11
• Chapter 10 — Commission 10
• Chapter 9 — Commission 9
• Chapter 8 — Commission 8
• Chapter 7 — Commission 7
• Chapter 6 — Commission 6
• Chapter 5 — Commission 5
• Chapter 4
• Chapter 3
• Chapter 2.5 — Volume 1 Extras
• Chapter 2 — Commission 2
• Chapter 1 — Chapter 1
• Chapter 0 — Prologue