Cuffing season
Cuffing season is typically defined as the time of year when single people actively search for short-term romantic partners to spend the colder months with, typically (in Northern Hemisphere locations) from October through March, culminating with Valentine's Day. The term "cuff" is slang that alludes to handcuffs and means metaphorically to attach oneself to another individual.
Cuffing season usually commences at the start of autumn when the weather starts to become prohibitively cold for outdoor activities. The lack of sunlight, outdoors, and warmth may lead some single people to become lonely and desperate. In addition, being in a relationship in the winter months allows for companionship during holidays. The rise of dating apps like Tinder further contributed to the phenomenon. However, engaging in such a relationship with a superficial basis may lead to emotional drama for some people in the long term.
There is no evidence that cuffing season has a biological basis, but psychological factors likely exist. It is possible that there may be hormone changes during winter that relate to the phenomenon. The colder temperatures and darker days may affect melatonin and serotonin levels which theoretically could affect one's mood in a way that leads to cuffing. According to Facebook data, people often change their relationship status to "in a relationship" between October and February, and a significant number change it back to "single" in March. One study from The Girls Chase found that two out of three cuffed partnerships end by June.