The wiki for between_thighs says the tag is for objects held between the thighs, and that between_legs should be used when a whole person is in this position. However, going through each tag, it seems that they're just both used in the same way, according to the between_thighs wiki entry. So it's unnecessary to have both of them serving the same function.
Between_legs currently has 65 pages of posts versus 35 pages for between_thighs. And there are only 3 pages worth of posts tagged with both of them. Between_legs also has three tags that implicate it: hand_between_legs, tail_between_legs, and cat_between_legs. Considering this, I think it's best to just merge the two tags with between_thighs aliased to between_legs. Unless we really need a tag for someone between another person's legs (and I would suggest making a new tag for that anyway, as it would cause less confusion).
What do the higher-ups think?
Updated by jxh2154