You're not supposed to believe it. You're not supposed to believe any of it. Did you completely miss all of the little annotations and arrows pointing out the ridiculousness of pretty much every silly, unbelievable situation? This mangaka does this sort of thing a lot - over dramatic, silly, ridiculous. They're fun departures from reality for those with a certain sense of humor.
Maybe that is your intention , not to believe the story context. However I do like to relate things to reality. We are 2 different people who both enjoy Yaoi as genre but we are looking at different aspects that satisfy our imagination.. I’m not saying that I don’t enjoy comedy however it is a secondary element to any story I read , however ..In my opinion this story relates to those Adam Sandler’s types of movie which I do not enjoy .
I don’t have experience with this Mangaka style of writing techniques. i give her/him credit for imagination. But silly, over the top type of events are not my cup of tea
( ̄∇ ̄") er... you're a very serious person, aren't cha

A lord with a great legacy and huge amount of debts faces the care-free, rude and obnoxious [Shou] .. Th way how they jumped into doing it .. is lame and unbelievable. I can't imagine somebody who is bound 30 and never heard of the word Sex and on top of that he is English ..