Revisiting this classic is making me feel things 😭
Imagine putting the ramping tension between Light and L into Suguru and Satoru's dynamic...
Imagine a SatoSugu Detective AU
If I actually executed on this (which I probably won't), I wouldn't exactly put Suguru in the criminal shoes... I'd probably cast him as a Moriarty type of character (from Moriarty: The Patriot).
Suguru would willingly cast himself as the bad guy to save something/someone or uphold an ideal. He would be a Lelouch character in this AU, and also basically do what William Moriarty did.
Satoru -- the renowned, brilliant, eccentric detective going around solving the most difficult criminal cases. It would suit him... Canonically, he does have heightened perception, and in a Detective AU, you could also add impeccable deduction to that list. He would be the Sherlock type of detective. (I can't see him being L... L is L 😝 No one replaces my L Lawliet)
Satoru figures out what Suguru's actually trying to do and sees him as more than a rival, but as an equal and a friend.