I like how the ML isnt a generic black haired Hero type nor is he a OP shota.
he has a subtle OPness that he's not that clueless yet not that strong either.
i think some are forgetting, she's not a concubine but a second QUEEN. Her child will still be under the imperial family. the sole problem of his legitimacy is that he's not traditional blooded. but The king is half and its not as if traditional blood has powers that he couldnt be heir.
OOF Author i'm not sure how you want the readers to feel. intro events are annoyingly placed. I guess its too early to start the series. I hope it gets better soon.