If you like the artwork but is concerned about the age gap- Ive read a few chapters of the novel and if i remember correctly the age gap between them is not as big as it seems. The 'bride' (ml) has a smaller build than his actual age, though the manhwa shows him even smaller than that which is kinda freaking me out. I think ml was around 13 but lies that he is older and mc is 16. Its still a fucked up situation that 2 KIDS are getting married, but then the entire situation surrounding the royal family and mc's father is vile so its kinda expected.
Till the part where i stopped reading, there is no romance between mc and ml, mc is just focused on trying to make sure ml and other people around him survives the kings madness, while the ml is extremely distrustful of mc in the beginning. The romance part does not come in until much later i believe.
Though, fair warning, the king is portrayed as a sadistic tyrant, so there might be some triggering situations or scenes at some point in the story, not sure since i havent read that much ahead

The only thing that seems good about this is the art style. Cause wdym that child is supposed to be the ml…. Ik that the ‘romance’ stuff is supposed to happen later, but it’s js weird seeing the age gap when their literal kids instead of knowing grown adults.