Despite the debacle of AC "experts"
its indeed true that in past era, both chinese and jp, did lot of "yaoi" sex.
And one manga or novel, mentioned, that yes, there were shotas in their "harem" or "prostitute".
tldr : imagine the modern west priests and their "crimes"
On nu I look at a cover, and if it is a CN with characters on it, men usualy look delicate, with long hair and fine features, in long robes like dresses. Many a time I thought it was a waifu on the cover not male mc
With JP it's a 50-50 case
And KR covers generally feature manly men mc's
What do you mean ?