The 'Super' part is because of SuperGrover. My husband and I, once had some silly spat, and knowing my love of all things Jim Henson, He did a Grover 'Near,....Far' impersonation, that had us both laughing until our muscles were sore. Needless to say, the spat was over.
It`s a good memory, that brings about many 'Super' jokes.
JA is the first 2 letters of his name, and ST is the first two letters of my name. 'JAST' has been used when we do anything together. When I was pregnant and we didnt know what the sex of the baby was yet, we called the baby, 'JAST'.