No Hugging, No Kissing, No PDA of any kind!
The penalization of romance stems from the idea that The Power of Love either Makes You Evil, Crazy, Uncreative or just plain Dumb. Love just seems like a bad idea, so what better way to better the human condition than just banning love altogether?
This is a strange, if-not impossible law to regulate and enforce in real life, so those that enforce it are foolishly idealistic at best, unreasonable and tyrannical at worst, inspiring various rebellions of various shapes and sizes in the process. The Evil Overlord behind it could have a variety of reasons for doing so. They could have had a personal experience with failed love, thinking that if they can't have love, then no one can, or maybe they feel that they are committing a service to others and preventing heart-break. If completely eradicated from society, people could ask "What Is This Thing You Call "Love"?"
Should the love banned be physical, then it's No Sex Allowed, or at least No Heterosexual Sex Allowed to keep the population down or because of a Persecution Flip.
- It's considered taboo for Succubi and Incubi in Fine Print to feel or express love because it can become addictive to their kind. Even familial love is off-limits, preferring to show pride or respect.
- Because his own love was spurned, even after trying to use a Love Potion, the Bog King from Strange Magic bans love from the Dark Forest and imprisons the Sugar Plum Fairy, making sure that the Love Potion is never made again.
- After Queen Freya from The Huntsman: Winter's War sees her lover Andrew murder her infant daughter when in actuality, he was being controlled by her evil sister Ravenna, she kills him with her dormant magical powers and conquers the north. She then abducts the children of that land, trains them into her own, personal army, and then makes love a crime punishable by death.
- The state of Libria in Equilibrium criminalizes love alongside all other emotions, and legally requires the population to take emotion-suppressing drugs. It is strongly implied, however, that even drugs cannot fully eradicate human capacity for love, since even John Preston, who dutifully took them all his life, displayed behavior consistent with emotional reaction when the state took his wife away from him.
- Played with in the Delirium Series. Love itself (the novel's focus is romantic love, but it's made clear that it applies to all love) is a mental illness, and objecting to the "cure" is considered criminal.
- Both physical and emotional love are forbidden in 1984 because the only acceptable attachment is devotion to Big Brother.
- In the Free-Love Future of Brave New World, not just monogamy but feeling too strongly attached to someone is highly frowned upon and considered backwards and unnatural, if not outright illegal (Lenina's friend encouraging her to be "more promiscuous" to avoid trouble could very well mean "be more promiscuous so you're not suspected of breaking the law").
- The Peacekeepers in Farscape are totalitarian Commie Nazis, and a totally military society who use The Spartan Way for upbringing. While non-procreative sex is accepted as a form of physical recreation, any form of emotional relationship beyond military comradeship is absolutely banned. When one female character was discovered to have fallen in love with a man and conceived a child by him without eugenic selection, she was forced to choose between killing her lover or child.
- According to one Christian legend, in 3rd century Rome, an emperor by the name of Claudius issued a decree to his soldiers that they were forbidden to marry. A guy named Valentine defied this decree and issued marriages to the soldiers in secret. Claudius found out, was furious, and had Valentine beheaded. Thus, one theory on how the legend of Valentine's Day was born.
- In Once Upon a Mattress, Queen Aggravaine passes a law banning her subjects from marrying until after her son is married, in hopes that her subjects will be inspired to find a suitable princess. Since the women of the kingdom aren't interested in being wooed unless there's a hope of getting married, the marriage ban effectively serves as a ban on courtly love as well.
- In The Mikado, the emperor has decreed flirting is punishable by death. As of the beginning of the opera, the authorities have been getting around this by appointing Ko-Ko, a condemned man, to the office of executioner. Since he is the next man scheduled to die, no one else can be executed for flirting until he is, and since he's not planning on executing himself, there have been no executions.
- Haven (2020): The Apiary has a government branch known as the Matchmaker that pairs up individuals it deems compatible as "mates" and declares romantic relationships outside of these pairings illegal. The plot is set in motion by protagonists Kay and Yu fleeing the Apiary to pursue a relationship with each other rather than their assigned mates.
- The plot of the H-Game Kimihagu has Emily Yūki, the daughter of the school principal, becoming the disciplinary committee president where she forbids all romantic behavior on school grounds, forcing the "Love Club" (where they study love and all romantic behavior) to hide in the basement of the school church. She means well and the "crime" is ultimately downplayed, but she turns out to be a total busybody.
Emily: (blowing whistle) Both of you, being in a relationship is against the school rules. A student's job is to study. Love can wait. As long as I'm around, I won't allow anything that destroys our school's morale!
- In Steam Prison, the population of the Heights is strictly controlled by the government, which arranges all marriages as part of this system. As a result, romance or sex with anyone other than one's designated spouse is a crime that can get you sent to the Depths. This is how Rielith ended up in the sanctuary district, and why poor Fin can't admit his feelings for Cyrus until it's far too late. It also means that Cyrus, the heroine of the story, is largely clueless about anything related to romance or sexuality.
- Some very extremist totalitarian regimes took control of everything, including who can marry, how and when, and repress sexuality, cases like China during Mao's Cultural Revolution, Pol Pot's Cambodia, and to a lesser extent Stalin's USSR.