Kenshi is lacking some of the finesse when making a multi-person chair for example.
Kenshi does allow multiple characters to sit on an object, but there is no offset option in FCS for each sitter. Characters would sit on top of each other.
But we got two options:
A) a female and a male skeleton (or any two or more different skeletons*) can sit on a single object nicely side by side, if the sitting animation is made so that the bone positions are saved a bit aside from the origo, the other left and the other right. AKA in-building the offset to the animation. Both animations are saved on the animation strip with the same exact name.
B) any amount of characters can sit on a 'church bench' if each character has their own chair. This would mean the bench is divided in several mesh parts, which are each a seat. No, you cannot make that a single object with several parts, just does not work that way. It would mean the person setting up the bench would have to manually place each part side by side.
Many modders are able to set up their interiors like this easily, but not many players have those skills. So the player could hardly build the bench precisely, although it does not really have to be perfect. But would surely frustrate many. It may be possible to set all the bench parts to link to each other, have not really explored this, but all the pieces would have to be identical and stand alone. I have not tested this with animation functions.
*Technically it would be impossible for the player to know which characters of theirs have different skeleton, resulting in an experience of 'sometimes it works, sometimes it does not'. So far easier for all players to understand, is to use this only on animation pairs that are traditionally male and female animations, like a wedding, ball dance, etc. Gay marriage would require the option B.