Medieval Christian polemic held Muslim sexuality as a core mark of heresy.

Evidence

In Abbot Joachim’s prophecy, just as the heretics were opposed by the doctors of the Church, so Muhammad was opposed by the virgins. The special lubricity of Muslims was everywhere believed to be a fact, and this, of course sprang from the teaching and example of the Prophet, which the Qur’an preserved. — Norman Daniel, Islam and the West, 805

Categorization

• ADDENDUM: Connects directly to ‘Complaints About Immodesty Go Way Back’ — this is a medieval Christian cousin of the moral-panic-over-dress pattern, here aimed at Muslim sexual reputation.
• XREF: connects to: Christian polemicists portrayed medieval Muslim sexuality as wholly unregulated