1. Pheromones and Natural Body Odor
Natural scent compatibility: Everyone has a unique body odor influenced by genetics (especially genes in the major histocompatibility complex, or MHC). Some people are instinctively drawn to others whose scent signals genetic compatibility.

"Bad" isn't always bad: What smells bad to one person might be intoxicatingly attractive to another, especially if it's linked to those compatible pheromones.

2. Psychological Associations
Taboo and kink: For some, being attracted to "bad" smells ties into fetishism, dominance/submission, or taboo-breaking themes, which can heighten arousal.

Early experiences: Sexual preferences can be shaped by formative experiences. If someone had a strong emotional or sexual connection with a person who had a specific body odor, that scent might become eroticized over time.

3. Scent and Authenticity
Raw, primal attraction: Some people associate body odor with authenticity, intimacy, or raw animalistic sexuality—an unfiltered version of someone.

Sweat as a signal of arousal: Sweat contains compounds that may signal sexual readiness, which some may unconsciously pick up on.

4. Cultural and Individual Variation
Cultural norms: What’s considered a “bad” smell varies widely across cultures and individuals. In some subcultures, body odor is embraced rather than masked.

Desensitization and preference: People who live in close proximity to others without heavy hygiene rituals may develop tolerance or attraction to stronger body odors.

5. Biological Reactions
Hyperosmia (heightened smell sensitivity): Some people have more acute smell perception, making them more attuned to subtle variations in scent that others find repellent.

Hormonal influence: Smells can interact with our hormones and brain chemistry in complex ways, influencing mood and arousal.