Harem is more similar to an extended relationship, where consensual sex between members is already part of the harem definition:
- Harem [1 person being courted by at least 3 others, all engaging in consensual sex simultaneously.]
So swinging doesn't apply
as long as the characters are being
added to the harem
before fucking them.
Now
some harem games may allow for member to have sex for fun even with people
outside of the harem (
third party), that's when the swinging tag also applies, will depend on how people perceived the situation in question.
But in most cases the intent is to simply add more people to the harem what isn't necessarily swinging/sharing but just classic harem logic.