🎃 Nerd With Fangs 🎃

No, it's the fact that Klavier was the prosecutor for the case that ended up with Phoenix disbarred. Because remember, before everything, Apollo idolized the hell out of the guy.

Servants of the royal family also have the diamond tattoo, such as Nayna and an unnamed Royal family servant that appears when Inga stamps the execution orders in Case 3 near the end of investigation day 1.

Tahrust and Beh'leeb's baby, Faitah, is also shown to have a diamond tattoo in the end credits while baby Rayfa didn't have one. Could be in the case of Rayfa that they didn't have the opportunity to add it before she and Amara were taken away.

In the anti-Defiant Dragons propaganda, they depict Dhurke without his diamond tattoo.

The murals in Amara's tomb are particularly interesting to me, because Amara is shown to have lost her diamond tattoo after she met Dhurke, without a doubt playing into the propaganda that Dhurke corrupted her. She's also shown without her cheek markings as well, so it's not like this was a cultural change that was meant to be hidden.

As for why Nahyuta's forehead tattoo looks different to every single character in the game, my personal theory is that when the fire happened, he didn't have the tattoo yet and only had it while living on the mountains with Dhurke, Apollo and Datz. Kind of a "Fuck you my son is still part of the royal family" deal, just without the usual finesse of making a traditional diamond tattoo. However, this part of his backstory is pretty ambiguous, so it's really hard to gauge.