I have to cordially disagree. The story is set in the end of the 19th century in France, not in a shady country in a dark version of the european middle-age. Woman right activist exist and fight heavily at this time ( It was the moment when women obtain the right to go to school, to work and start to fight to gain the right of vote. ).
Soooo if the author wasn't more take up to show us how everyone want the omega's ass of Chris, she could have show us some omega right activist trying to fight, and describe a society where being an omega was indeed a pain in the ass, but where thing starting to slowly change.
Actually this manhwa is not based on modern world
If we read modern world omegavers where mc is omega
No one will rape him because in modern world there are many laws and every individual has right (except north Korean citizens)
So if we think it like this
Then mc getting raped is understandable
Because he is just weak omega who has no one
So every alpha is taking advantage of him
If he was born in modern world this will probably change