From ep9 of Prison School where Kiyoshi was asked to give the reason why he preferred ass over boobs.
Back when we still walked on all fours, we always had in front of us… the butt. Then from the time mankind started walking on two legs we stopped having butts stuck in our faces all the time, and in their place, what appeared in front of our faces… were boobs! Women grew larger breasts to take the place of buttocks. The original source of life is the buttocks!… BOOBS ARE NOTHING MORE THAN A PALE IMITATION OF THE BUTTOCKS! IF ASKED WHAT YOU’D RATHER HAVE, A COPY OR AN ORIGINAL, NATURALLY, I WOULD CHOOSE THE ORIGINAL!"Mankind...
Back when we still walked on all fours, we always had in front of us... the butt.
Then, from the time mankind started walking on two legs, we stopped having butts stuck in our faces all the time, and in their place, what appeared in front of our faces... were boobs!
Women grew larger breasts, to take the place of buttocks.
The original source of life is the buttocks!
Boobs are just a substitute!
Boobs are nothing more than a pale imitation of the buttocks!
If asked what you'd rather have, a copy or an original, naturally, I would choose the original!
Boobs jut out forward due to the process of evolution, keeping the buttocks further back and to the rear hidden!
However, that is where the grace of the Eros of the buttocks is..."