“There is no substantive-due-process right to stimulate one’s genitals for non-medical purposes unrelated to procreation or outside of an interpersonal relationship.”
-From a 2007 legal brief filed by Ted Cruz’s office when he was Solicitor General of Texas (via Mother Jones)
“It’s simply a matter of freedom of pleasure, a right which is not guaranteed by the Constitution, unfortunately.”—Tom Lehrer
OTOH, laws against dildos might violate the 9th Amendment (is it a liberty “retained”) and federal laws would definitely violate the 10th Amendment.