Why do I have to pay more for this?

"Why is this twice as expensive as your regular manga?" a customer asked me yesterday.

On the counter between us: a hentai magazine from the section where we keep the naughty books; the cover prominently displaying drawings of young schoolgirls undressed and in rather 'mature' poses.

"Well... uhm," I stumbled;"I guess this falls more into a niche market and the regular manga we purchase with bulk prices."

"Hehe, you said bulk," he giggled.

"Uhm..." uhm, indeed.