I originally thought all those malevolent ghosts were because he fought in the war or the holy sword. After that chapter I think he is cursed as well. Look how his room has the most dense ghosts and they're really persistent even after MC wards them off, it started happening only after he ascended the throne and there was a child ghost i dont think he would kill a child. His brother looks sus asf but I also think it's a bigger problem than just a fight for throne with how that founding emperor acts mysterious.

The younger brother Prince Edgar and that tan skin foreign friend he has...
Like.. the way Rodrick's room was infested with malevolent spirits again the day they left the palace for the West Border is suspicious... the foreign friend was giving off dead face vibes...I know Rodrick treats his brother good but who knows what's hiding behind Edgar's smile.. if he's more into scholarly things like MC said then my bad but who knows..? maybe it's the foreign friend and he's using Edgar... but the whole thing was just suspicious.. it's like someone is cursing Rodrick to be overtaken by mania so Edgar might be placed on the throne to replace Rodrick...
All in all just keeping that scene in mind cuz I find the whole thing so suspicious.