Bisexual men stand at a distinct intersection of stigmatisation, and binegativity is a unique social problem distinct from homophobia. This thesis scopes the breadth of binegativity and its various forms, developing a typology and exploring plural understandings of bisexuality. Drawing on 17 semi-structured interviews with bi+ men and their partners (25 participants overall), experiences of binegativity are explored, with romantic relationships analysed using interpretative phenomenological analysis. Despite no explicit questions about prejudice, all participants reported experiencing binegativity, often unakin to homophobia, both implicitly and explicitly, the latter as threats or acts of violence from strangers. In contrast, implicit binegativity denies bisexuality’s existence, and was displayed by close family, whose understanding of bisexuality was overshadowed by stereotypes, and participants were burdened undoing misunderstanding through education. Romantic relationships were sites of safety, positivity and growth, with identities being explored and developed, mutual understandings reached and experimentation outside of monogamous, heteronormative and patriarchal relationship structures negotiated. Some participants relayed that their partner choice was in some way shaped by heteronormative family expectations. Identities were often expressed plurally, with participants often expressing at least two sexual identity labels simultaneously, some of them contextually used over others. I conclude that bisexual+ people suffer epistemic injustices which exclude them from articulations of LGBTQ equality and same-sex marriage debates which emphasise monosexuality, sameness to heterosexuality and fixity. I suggest that education is a possible avenue away from binegativity, along with everyday articulations of bisexuality that challenge a status quo characterised by binary thinking about gender and sexuality.