Reasons you should give "King's Maker" a try if you love "The Captive Prince" series
and vica versa of course
The similar elements
M/M romance + "struggle for the throne" plot
Plot has well written characters & is dense with intellectual warfare like CAPRI (yes really.)
Creep "Regent" in this story too yes.
Both are completed stories with a focus on story first, romance second
political intrigue, horsies!, CSA (implied not explicit), mature content, mental illness, includes fantasy elements (which are not in capri)
Both characters are NOT royalty, only one of them is (just a warning since that is a significant dissimilarity from CAPRI)
With respect to romance i think the similarities run deeper than the basic "sunshine x cold" troupe in the best way
Just like Damen, Wolfgang is initially naive to the workings of the court, all he knows is that he can put his trust in Soohyuk and that loyalty and fierce urge to protect the other comes as naturally as breathing.
Just like Laurent, Soohyuk is intensely complicated and at times self sacrificing (especially where Wolfgang is involved). His plans to annihilate the enemies of the throne make the story amazing.
I think Laurent's love for his kingdom and wanting peace for his people is what he shares with Soohyuk. They're larger than life characters, even more so then Damen/ Wolfgang (The designated himbos - forgive my umbrella term-ing them).
