
ok, re-read the first ch… so this school-temple was built to raise warriors to defeat a dragon, that hasn’t even hatched yet?
but that means after the prince’s death, they were supposed to send another one? now i have even more questions. who are the other kids, wy there'sso many? why didn’t the school’s rules change after years without dragons? how many children is house supposed to send per generation? how long is a "generation" anyway?!
haha, sorry, got carried away... forget this, i’ll just play little game with myself from now on - if someone starts crying in the next ch, 24 betting on yes, 25 no ang yes yes...
(=・ω・=)

lol... idk if i know all the answers but will try my best to answer. the prince hasn't died yet - he will drown (when i don't recall) but the MC is stuck in that castle lone when that happens & afterwards the Kings brother invades killing him to take the throne.
either way the MC wasn't sent in his stead, cause he was dead - as for now he is alive & well just besides his father (& we have never really seen the prince).
about the other kids, what i remember is that they from other kingdom's, the monarchy's progeny & other high statues people's children. maybe in the book all this info exists about what the school rules were or why they changed. how many to send per generation? etc.. i don't recall if this info being mentioned in the webtoon. sorry couldn't be of more help

So basically... from what I get... the last dragon was killed by 5 heroes with the support of the temple... that went on to become the royal family of 5 kingdoms and the temple keeping an eye out for dragon related things. Idr if the temple made a school that became a tradition for nobles to attend or if they made it especially for this generation, but! Recently a dragon egg was found and the temple demanded that one child from every (noble I presume) family to be sent for training. Especially the 5 royal families that descends from the heroes.
The current king of Mc's country is her uncle and came to power by usurping the throne. The original kimg, his older brother pretends to die and go into hiding with his sons. He have one child, the original Leo whom he spoils rotten and refuses to send to the temple in fear something dangerous happens to him. So he forces mc to pretend to be him and go instead while keeping her identity a secret. He cast a spell on her that keeps her from telling others.
In the original story a bit after she returns the original Leo gets poisoned and dies. After that the original king comes back and take back the throne killing the current king while at it. He keeps mc alive but neglects her maybe even more than previous king because mc's mother was mean to his late wife. Mc suffers for a bit longer before falling into a lake and dying too.
Right now the story is at the point after she gets back and before original Leo dies. And as the others think she is Leo and she can't reveal the truth, she'll have to stop keeping contact with them after the original dies. Then she plans to use the chaos of the original king coming back to run away and escape her fate of suffering more and end up drowning in the lake.
That's what happened until this point (ch24).

thank u for this summary, it's been a while since i started reading this so knew most of this but forgot lol.
just i was sure the prince is the one that drowns & the MC gets her head chopped off cause she takes/steals the doll of the adoptive daughter of the King... either thanks now wont have to reread this (●'◡'●)ノ
why exactly king make her an imposter prince, and "kill" her couple of years later? that doesnt make sense, why bother? mb it wouldve been better to keep up the act… or was there another prince?