A woman who is sexually attracted to middle aged male cyclists in lycra (see MAMIL).
Woman 1: "When I see that pack of sweaty old men in tight lycra fly past on their $10,000 bikes, I get so turned on."
Woman 2: "OMG, you're a mamilsexual!"
Usually used as an insult (the "mayo" referring to mayonnaise), a mayosexual is a morbidly obese person whose hormone disruption and physical changes from excess adipose tissue (fat cells) has caused them to lose their sexual capacity, identity, and/or interest, and to become fiercely argumentative if it is identified that they have any physical weight, mental, or sexual health problems.
This is usually in reference so someone who is non-binary, has a disagreeable personality, has unnaturally colored hair, and has a markedly androgynous appearance.
Pride march used to be so hot. Now there are so many bears, big butches, and mayosexuals on scooters.