So in RL I can share clothing with my partner, it would be cool to do the same in SL. Limit it to being an action only available for Official Partners on SL, this would limit it to being between only two avatars, it doesn't transfer ownership it just allows us to share inventories for avatar attachments only and this means we could share clothing together. This could also incentivize makers to make product lines that are couples enhanced or something. I just know my Partner and I would totally enjoy a feature like this because we both have great stuff and some things we own can't even be bought any more but it would be fun for the other to wear it for a picture and such.
Maybe it could be a limited to a specified Partner folder (similar to RLV outfits) where anything put in there can be attached by the owner's partner avatar.
Once the partnership is over, that feature no longer works between them because it does not transfer ownership of the items in any way.