OBHWF

From Fandom wank wiki

Abbreviation for One Big Happy Weasley Family.

The term refers to a concept in Harry Potter fandom that endorses Harry/Ginny and Ron/Hermione. Because Ron and Ginny are siblings, this would have Harry and Hermione joining (well, dating) the same family. In other words, R/Hr + H/G = OBHWF. (There's probably a numerological 666 in there somewhere.)

Of course, some definitions include more than just those two pairings. Sometimes fanfic expands the Weasley family exponentially, with Bill/Fleur, Charlie/Tonks, Percy/Penelope, and the twins/their Quidditch teammates. Double or triple weddings are often a feature, as are multiple christenings and Snape cutting his throat after every new year brings another seven Weasley offspring to Hogwarts. (Generally, fanfic like this is boring, and is frowned upon by normal people, simply because it is het.)

OBHWF is diametrically opposed in shipper wars to Harmony, which would put Harry together with Hermione and cast Ron and Ginny into the seventh level of hell for all eternity. The dispute as to which ships were canon raged on until JK Rowling went with OBHWF. Then the dispute turned into good, old-fashioned wank.