Since people apparently don't get it, an explanation:
This was shown during the ED theme song of Kannazuki no Miko, a very famous anime for popularizing a main character yuri relationship. (At a time when lesbianism was either only hinted at, or done by side-characters who were either evil and/or died at the end, and were shown as dying specifically because being a lesbian was evil, and they needed to be punished for it.)
Practically by definition, parodying this pose is a reference to a lesbian relationship, which is why, well, you see it used with plenty of lesbians or characters ship as lesbians.
This was shown during the ED theme song of Kannazuki no Miko, a very famous anime for popularizing a main character yuri relationship. (At a time when lesbianism was either only hinted at, or done by side-characters who were either evil and/or died at the end, and were shown as dying specifically because being a lesbian was evil, and they needed to be punished for it.)
This, along with Shizuru and Natsuki of My-HiME, pretty much blew the doors wide open in regards to lesbians in mainstream anime where both the characters and the relationship survive at the end.
