Any scene that clearly demonstrates 2 (or more. I wont judge) characters that not only like each other, but like like each other.
The romantic attraction must be clearly obvious to most viewers even if they don't know the characters very well or understand the history behind their relationship.

Romantic activities include (but are not limited to):
affectionate embracing,
hand holding,
doe-eyed glances at each other,
kissing,
et cetera.


Note: The first half of this is romantic. The second half, not so much.

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