『Fangtasia』's manga / #Magic(21)

KING SEME X SLAVE UKE SHOTA TIME TRAVEL ADULT X MINOR Uke too young (cultural reference maybe? IDK much about meditteranean or MEAsia) King's harem, boy replacement for sister. The novel says Seiji is 12 or 13 & the love triangle will happen WITHOUT TIMESKIP. WARNING for underage sex. I've put off reading this because I know it's received heat for a shota storyline, but since it also has great reviews around the world-building and the rest of the plot I wanted to give it a read to see what's up for myself.