Bisexuality has long been considered the “invisible sexuality”. Its unseen nature ranges from general public discourse, to academic under-representation, and even inner-community politics. While bisexuality remains the unaddressed letter within the LGBT acronym, I argue that to be rendered invisible does not negate suffering from a simultaneous – and potentially far more deliberate – rejection of bisexuality as a legitimate sexual identity. To fully explore the parameters of systemic wrongdoing to the concept of the bisexuality, this chapter focuses on the theoretical aspects of the injustice done to bisexuality via several frameworks. First, I draw upon the epistemic injustice faced by bisexual individuals regarding how their lived experiences – and therefore their knowledge about their own marginalisation – are reduced by those in the hegemonic positions, hereby diminishing the bisexual’s power as a legitimate “knower”. Second, I discuss how the bisexual (dis)position of power is further challenged by structurally addressing bisexuals as the non-dichotomous “other” in a binary structure of sexual identities, and examine how this leads to a struggle of identity negotiation.