
Wait, I forgot what Sylvenian did in past life? Like how did he live previously

It was mentioned in the earlier chapters that he was previously tossed aside by Rosie in 3 years after she claimed Mikael. It's likely he suffered some form of negative effects after getting tossed aside post-imprint (eg. depression etc). Or he went back to being a guard but with PTSD from all the SA he received from Rosie. But seeing as how the royal family treats their kind like toys Rosie may have lost him in a bet, had him fight other homoculi as a disposable pawn, or as mentioned by Haru above sent to do labor. It wasn't really elaborated since the focus shifted to Mikael and Rosie but yea. I don't think it he lived well after.
Dyne thinks of Kouichi during sex with Rail in ch 109. Literally went back each chapter to make sure I was not imagining it. I want to know what he thinks of Kouichi.