In past decades intensifying concerns over the definition of moral order have afforded the “newly pious” in Niger unprecedented control over the terms of moral regulations in the public arena. How such control has translated into close scrutiny of Muslim women’s sexuality and mobility has been well documented. Less clear is how the so-called piety turn has affected Christian women’s understanding of virtuous womanhood. Notwithstanding the animosities that routinely shape Christian and Muslim relations in Niger, an overwhelmingly Muslim country, the lives of Christian and Muslim Nigeriens are entangled in complicated ways. Inspired by recent attempts to develop a conceptual framework for the joint study of Christianity and Islam in Africa, I trace Muslim and Christian Nigeriens’ shared anxieties over women’s moral frailties through a focus on Pentecostal Christians’ and Muslim reformists’ responses to spiritual attacks that have taken place in schools and other settings. Both Pentecostal Christians and reformist Muslims wish to distance themselves from local practices centered on the veneration of spirits. As they see it, possession and its cohorts of symptoms signal the workings of Satan's servants who must be resolutely combated. Women who are inherently susceptible to evil forces yet also allegedly bear some responsibility for the recrudescence of spirit attacks emerge as both symbols of compromised integrity and instruments of moral reform. By considering evangelical Pentecostalism and reformist Islam as doppelgängers—adversaries whose fate are intertwined—as was suggested by Brian Larkin and Birgit Meyer, I explore the multiple conversations and confrontations in which Islam and Christianity—in their various configurations—engage both within and beyond their respective "boundaries."