Why is shimapan so arousing /a/?
The stripes display the contours more clearly, like a topographic map of her butt.
I like slutty lesbians that actually love cock.
Horizontal stripes display curves very well, making things appear more voluminous.
Also shimapan is a rather childish and playful design, so it evokes feelings of youth and innocence by association.
I take it you're an expert
You've seen it used erotically so many times that you already feel aroused just from the pattern itself. Pavlov's dog etc...
You were conditioned.