It's like this:
Figurative: Ni
(I don't know what Se is)
Creative: Ne
Literal: Si
See how I describe functions by sort of labeling it in a really simple single-meaning way? that's Si. INFP has tertiary Si so that must be it.
But in order to really understand this, you have to look at the differences between Pi and Pe. Pi deals with meanings, forms, and concepts(something that has a form) while Pe deals with connections, streams, relationships etc.. When you're talking about figurative vs. literal, you're talking about things that are purely definitional or semantic-related, which is Pi. It's something that is "perceived" instead of something you are currently "perceiving." INTP's likes to "establish" things by pointing out the truth behind things, and the best function to "establish" a meaning is Si. You can see this going on a lot in mathematics. The symbols in math are not some mystical voodoo shit(although the proper term would be "non-contextual"), they are universal meanings with single-definitions to be used in all conceivable mathematical context(which is technically only one context) and are consistently being "related abstractedly", now that is Ne. Ni, on the other hand, does not like to establish meanings.