What does that mean?
It can mean a bunch of things, but from my experience most people use it to describe a 'one-time meeting roleplay'. For example:
1. Two characters meet each other at a coffee shop. A robber comes in and a hostage situation unfolds. The two characters team up together to protect the other customers and eventually help the police take down the robber. After this victory the two characters shake hands and say their goodbyes, and the roleplay ends.
2. A knight stumbles upon a beggar on the street. The beggar tells him about the precious item that was stolen from him and is now on display in a shop. The knight and the beggar plot together to take the item back from the thieving shop owner and sneak in at night, narrowly avoiding detection and sneaking out successfully. The beggar thanks the knight and the knight is on his way again to find more people in need. The roleplay ends here.
The difference between one-off scene and long-term is that one-off scenes tend to be shorter and have a definite end/parting for the two characters, both temporarily and permanently. Long-term is when the characters are involved in a much longer game that goes on for a long time (for the characters and often for days/weeks/months for the players too!). Long-term roleplays also have endings, but they take much longer to achieve.
I just stated some clear-cut examples, but one-off might be played a bit differently for some people.
When in doubt just approach the player and confirm what they mean with it! Does this answer your question?
1. Two characters meet each other at a coffee shop. A robber comes in and a hostage situation unfolds. The two characters team up together to protect the other customers and eventually help the police take down the robber. After this victory the two characters shake hands and say their goodbyes, and the roleplay ends.
2. A knight stumbles upon a beggar on the street. The beggar tells him about the precious item that was stolen from him and is now on display in a shop. The knight and the beggar plot together to take the item back from the thieving shop owner and sneak in at night, narrowly avoiding detection and sneaking out successfully. The beggar thanks the knight and the knight is on his way again to find more people in need. The roleplay ends here.
The difference between one-off scene and long-term is that one-off scenes tend to be shorter and have a definite end/parting for the two characters, both temporarily and permanently. Long-term is when the characters are involved in a much longer game that goes on for a long time (for the characters and often for days/weeks/months for the players too!). Long-term roleplays also have endings, but they take much longer to achieve.
I just stated some clear-cut examples, but one-off might be played a bit differently for some people.
When in doubt just approach the player and confirm what they mean with it! Does this answer your question?
Thank you for the detailed answer! It helped a lot!
You're welcome! I also realized I made it sound like the characters have to be strangers - that's not true, they can be familiar with one another and meet up, do something and then go home too. 
I like to think of it as doing 'quests' in roleplaying games (like Skyrim) that have a start and end and are completed relatively quickly.
I like to think of it as doing 'quests' in roleplaying games (like Skyrim) that have a start and end and are completed relatively quickly.
Quote:
adjective
1. done, made, or happening only once and not repeated.
"one-off tax deductible donations to charity"
noun
1. something done, made, or happening only once, not as part of a regular sequence.
"the meeting is a one-off"
1. done, made, or happening only once and not repeated.
"one-off tax deductible donations to charity"
noun
1. something done, made, or happening only once, not as part of a regular sequence.
"the meeting is a one-off"
You are on: Forums » Help » One-off scene
Moderators: Mina, Keke, Cass, Auberon, Claine, Ilmarinen, Ben, Darth_Angelus