I'm personally of the opposite mind actually. I would much rather it remains as pure lust/trickery on Durrak's end once Valla inevitably spreads her legs and only ever goes as deep (heh) as sex friends at best.
Kohaku is the perfect example actually lol. How she remains firmly in love with the MC... while getting plowed by half the kingdom. It makes the cheating all the better in my book. Having Vallabelle falling in love with the other guy sounds so... boring in my book, it's the classic NTR way of things. It happens ALL the time already. It makes her cheating on her partner somehow weaker since her heart isn't with him anymore anyway. What's the point then? She's with him out of obligation or something at that point. But if she still loves her husband yet continues to cheat on him anyway? That's the real fun part for me. It's twistedly wholesome in a way lol.
