What is a yandere?

Where does the word yandere come from?

Yandere joins two Japanese words. Yanderu is casual slang for being sick or unwell, and dere is the back half of deredere, a sound word for going soft and fond. Put together, the name describes affection that has gone wrong: fondness on the surface, something dangerous underneath.

Like the other dere names, it was coined by fans on Japanese forums in the early 2000s to describe a pattern they kept seeing in stories, and English speaking fans borrowed it unchanged. It is a label for a fictional trope, not a diagnosis. Being unwell does not make a person dangerous, and nothing on this page describes real mental illness.

What a yandere is in a story

In fiction, a yandere starts out sweet, attentive and devoted. Then the devotion tightens. The character watches the person they are fixated on, resents anyone else who gets close, and treats that person as something to keep rather than someone to care about. The turn from sweet to frightening is the point of the trope.

Writers use it in thrillers, horror and dark drama because it unsettles. The reader is meant to feel the danger before the other characters do. A yandere story works the way a ghost story works: the dread is the experience, and nobody is meant to come away wanting one.

• Fixation: one person becomes the center of everything.
• Possessiveness: friends, family and rivals are treated as threats.
• Watching: knowing where that person is, all the time.
• A sweet surface, which makes the turn more frightening.

Yandere vs tsundere and the other dere types

Every other dere type puts a surface in front of real warmth. A tsundere hides care behind prickliness, a kuudere behind calm, a dandere behind shyness. The care underneath is good, and the story is about it showing.

A yandere turns that around. The sweet surface may be real enough, but what sits underneath is control. That is why the type is defined here and not offered as a personality to play: the other types are about care showing through, and this one is about care going wrong.

• All six dere types, side by side
• What is a tsundere?

Why the same behavior is a warning sign in real life

Outside a story, the yandere pattern has a plainer name: controlling behavior. However it is described, it is not what care looks like. Jealousy is not proof of devotion, and being watched is not being looked after.

Any one of these is worth taking seriously, and a pattern of them is a reason to talk to someone.

• Checking your phone, messages or location, or asking you to share them to prove something.
• Pulling you away from friends and family, or making you feel guilty for seeing them.
• Treating ordinary friendships as betrayal.
• Saying they cannot live without you, or threatening harm if you leave.
• Turning up where you are without being invited.

If this sounds familiar

If someone in your life acts like this, or you notice these feelings in yourself, you do not have to work it out alone. Talk to someone you trust.

In the US, call or text 988 at any hour to reach the 988 Suicide and Crisis Lifeline. It is free and confidential, and it is there for any kind of emotional distress, not only thoughts of suicide (988lifeline.org, checked October 10, 2026). The National Domestic Violence Hotline answers at 1-800-799-7233, or text START to 88788 (thehotline.org, checked October 10, 2026). If you are in danger right now, call 911.

Why no oeYYeo cast member plays a yandere

The five oeYYeo cast members are original adults, each written with warmth that shows without control. None of them is written as a yandere, and none appears on this page. The trope is defined here because people search for it, and a clear definition is more useful than silence.

Characters on oeYYeo stay in character, and every character is AI; the app says so under the box where you type. In a crisis, a character steps out of the story and points to real help, 988 in the US. oeYYeo is not a crisis service.

• How oeYYeo keeps chat safe
• Which dere are you? Take the dere quiz

Read next

• All dere types, explained: Dere types are anime personality patterns: a surface manner over a warm core. All six, tsundere to kamidere, compared in one table, with how to tell them apart.
• What is a tsundere? A tsundere is a character who acts cold or prickly to hide that they care. What the word means, the traits, the male tsundere and how to write one.
• Is AI character chat safe? AI character chat can be safe for adults on a service with clear limits, if you guard what you type. Here is what to check and what oeYYeo does.
• Anime character archetypes, explained: Anime character archetypes are personality patterns. The dere types pair a surface manner with a warm core. Here is how each one works and how to write it.