Fat fetishism
Fat fetishism is a strong sexual attraction to overweight or fat bodies, where a partner's size and softness are the main draw. Admirers are sometimes called 'chubby chasers' or FAs (fat admirers); the desired partner may be called a BBW or BHM (big beautiful woman or handsome man). It ranges from a simple, sincere body preference to more specific interests like feeding or gaining. Attraction to bigger bodies is common across all genders and orientations, though it's often stereotyped as straight men. At its heart it's just one of many valid body-type attractions.
For admirers the appeal is genuine — the softness, curves, abundance, and comfort of a larger body, plus, for some, the nurturing or indulgent dynamics around it. Being desired specifically for their size can also be affirming and hot for the partner.
Mostly it's ordinary sex and intimacy centred on appreciating the partner's body — worship, touch, and praise of their size and softness. Sub-interest couples might add feeding, cooking, or celebrating weight as part of the erotic dynamic.
The main considerations are respect and health: keep it affirming rather than objectifying, and be mindful that feederism or deliberate gaining involves real physical-health tradeoffs worth an honest conversation. As always, enthusiastic consent and body autonomy come first.
It shades into a few distinct sub-interests: 'feederism' (arousal around feeding a partner or being fed), 'gaining' (arousal from weight gain itself), and simple admiration with no interest in change. These are different things, and most fat admirers simply find bigger bodies beautiful, full stop.