Homoeroticism, yay!
Those moments of plot, dialogue, acting, etc., that fans delight in interpreting as homoerotic.
It probably originates from the old days, when the homosexuality taboo was serious enough that every gay pairing was considered a
Crack Pairing, so when authors wrote characters as very intimate with each other, everyone just accepted that they are just very good friends, and moved on, or when they wrote outright references to homosexuality, everyone just laughed at the sheer absurdity of the thought, and moved on.
With the emergence of
Yaoi Fans and
Yuri Fans, and the more open-minded writers, this changed forever. Nowadays, fans willingly interpret any interaction as potentially gay, even for characters without canon orientations and even for those specifically
stated by their creators to be straight.
Cultural differences also have their say here. The level of acceptable closeness between friends is hardly constant across various eras and nationalities, so, for example, the hugs and kisses which seemed mundane for a contemporary reader may appear blatantly erotic in the eyes of a modern one. In particular, the concept of
Romantic Two-Girl Friendship, highly intimate yet platonic, only began coming out of use in the latter half of the 19th century.
In the related trope called
Foe Yay, even
rivals or
mortal enemies can get this treatment by fans and writers alike, especially if they have
a more friendly past together, or one is
inordinately obsessed with the other. In
Fan Fic, this is the direct cause of many a
Slash Fic.
This trope does not include genuine ship teases or scenes of intentional Homoerotic Subtext between straight characters.
Examples:
