This is a characterization trope where a character is forced into the service of another through controlling a device, drug, or magic that keeps them alive. The "leash" is usually some sort of life support, a Restraining Bolt with built in Explosive Leash, or a chemical dependence that only the "owner" can supply. Usually this is used on good aligned or chaotic characters by evil ones, since this is too much a Jerk Ass move for a reasonably good character to use. Of course, if you need to keep the Token Evil Teammate on a tighter leash... In any case, the character likely hates being controlled, strongly dislikes or loathes the things they're forced to do... they just happen to value their life more than dying, though the sufficiently heroic will do a Heroic Sacrifice / Face Death with Dignity rather than fulfill a heinous order. If they can take a Zeroth Law Rebellion, they will, and if offered a means to cut the leash without dying, they'll take it. Compare Kid with the Leash. See also Jerkass Genie.
- This is a major point in the game Enslaved, the girl protagonist puts a slave collar on the hero that both forces him to obey, and will kill him if she dies.
- In The Avengers: Earth's Mightiest Heroes, Wonder Man was coerced into helping the Enchantress because her magic kept him from disintegrating.
- Rag doll in Sinister Six was kept in line because his employer supplied him with a cream that kept his skin from tearing off due to his contortionist abilities.
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