Campus sexual assault is a significant problem across the United States, and research has indicated LGBTQ+ students are at a greater risk of victimization than their straight-cisgender peers. Furthermore, LGBTQ+ students face unique barriers to help-seeking following an assault, including fear of stigmatizing the LGBTQ+ community. We propose that straight-cisgender allies may act as vigilant bystanders who notice signs of sexual assault and offer assistance to prevent assault from happening to LGBTQ+ students and/or to offer support after an assault occurs. Yet, research on the role of bystanders in preventing and alleviating sexual assault has largely overlooked experiences and perspectives of LGBTQ+ students. In this study, we explored LGBTQ+ students' perceptions of the roles straight-cisgender allies may play in alleviating the problem of sexual assault of LGBTQ+ students. We conducted group interviews with 30 LGBTQ+ college students from 19 campuses across the United States, paying attention to what they perceived as barriers to allies' help. Findings illustrate ways that boundaries between LGBTQ+ insiders and outsiders can leave both groups reluctant to make a "blind faith jump" to seek or offer help. We propose suggestions for how sexual assault prevention programming may bridge this gap between LGBTQ+ students and straight-cisgender allies.