The bulk update request #13409 is pending approval.
create implication sitting_on_arm (40) -> sitting_on_another (35060)
create implication sitting_on_back (254) -> sitting_on_another (35060)
create implication sitting_on_belly (96) -> sitting_on_another (35060)
create implication sitting_on_butt (106) -> sitting_on_another (35060)
create implication sitting_on_chest (209) -> sitting_on_another (35060)
create implication sitting_on_head (301) -> sitting_on_another (35060)
create implication sitting_on_lap (9248) -> sitting_on_another (35060)
create implication sitting_on_shoulder (140) -> sitting_on_another (35060)
create implication sitting_on_shoulders (178) -> sitting_on_another (35060)
Reason: All of the above tags should only be feasible with two or more characters, corroborated by the wikis that are available. Those that seem like they could be practiced solo would probably be better described by a lying_on_* tag or its aliases, as sitting is specifically regarding butt placement.
If this is to be accepted, I believe a consensus on implication #71372 comes first. I wasn't sure how to actually link them together (if that's a thing), so I apologize if I missed something. Or let me know if both of those would have been fine as a single BUR - I can edit this one and it would be good to know.
Updated