The bulk update request #11590 is pending approval.

create alias showing_hindquarters (0) -> presenting_hindquarters (138578)
create alias showing_rear (0) -> presenting_hindquarters (138578)

Reason: Adds two more showing_ alias variants to presenting_hindquarters. Of these, showing_hindquarters is tagged rarely but included due to its similarity to the base tag, and showing_rear is more common.

Tag history:
https://e621.net/post_versions?commit=Search&search%5Btags_added%5D=showing_hindquarters
https://e621.net/post_versions?commit=Search&search%5Btags_added%5D=showing_rear