Immersive virtual reality-based training and research are becoming more and more popular and are in continuous development. For instance, it is now possible to be trained by one's virtual self (i.e., doppelganger), meaning that a trainee can participate in a training program in which the trainer resembles the trainee. While past research involving doppelgangers showed promising results, findings revealed gender effects such that doppelganger-based training seems to be beneficial only for male trainees. In the present research, we contribute to this literature by investigating the emotional reactions and perceptions that people have when they meet a virtual human in immersive virtual reality. Specifically, we assess the extent to which the appearance of the virtual human (doppelganger vs. unknown avatar) and an individual's gender influence these reactions and perceptions. We found that males felt more positive emotions toward their doppelganger than toward the unknown avatar and that females perceived their doppelganger as less competent and warm than the unknown avatar. Our findings have important practical implications in terms of virtual reality-based training and research design such that the use of a doppelganger (unknown avatar) might be recommended in a training program or research setting involving men (women).