I am in the Determine the Relationship window. I have a steadfast MC. I chose the "considering something unacceptable" option. Is this just something unacceptable to the MC? The IC makes an offer to the MC that the MC considers unacceptable, so that works. Or is it necessary for the IC to consider something unacceptable, too, i.e. the refusal of the MC?
If you're looking at the relationship throughline, then "considering something unacceptable" would describe an aspect of the relationship. You did not indicate what story point you are exploring (e.g. Problem, Solution, Concern, etc.), which would allow a more specific answer since each is its own context to give it meaning.
For example, a Relationship Throughline Problem of Consider ("considering something unacceptable") would mean one thing, versus it being a RS Problem of Non-Acceptance, or a RS Concern of Contemplation, and so on. Plus, you may have it an attribute of the relationship ("the couple considers their current circumstances unacceptable") or something that is attribute to them ("a neighbor considers their relationship unacceptable").