In my opinion i Don't see cleaning as child labour, when i was young my mum would ask me and my siblings to clean the house, something we got pocket money sometimes we didn't. Also Theo is in a nice environment where he is not beaten given a comfortable place to stay and good food
Considering he was a child slave not so long ago, I dknt think it's the same. Why not send him to school and have him become and imperial scholar or something? Remember he's 10, and there's no other children in the Palace, so to him if he stops cleaning, they'll kick him out. Even if your parents ask you to clean up they won't kick you out if you don't, especially not as an 10 year old. I just think they could have had him do other stuff then clean as a child for a living
they have slaves in this setting, what is child labour? the setting of this manga is obviously not modern, and while for us modern people is might seem like a bad thing, a while ago, for a child to work was not a bad thing but an opportunity for that child. the time this story is set in were they still use carriages and fight with swords, child labour is not very mind boggling to be honest. (￣∇￣")
Modern or not I think child labor is kinda wrong. Even the maids aren't as young as theo. It would be a different story if theo wasn't taken in with chloe. If theo was working somewhere or was taken in a normal family that aren't nobles then house chores for the family would be alright.
Why on earth are they making him clean in the first place? Even though he may be getting paid its essentially child labour. The Palace doesn't need that sort of thing. Obviously they can't let him free load but it be better to give tasks appropriate for a child, like being chloe's butler, but with less task and more of a playmate