muffin[< muffin small biscuit or cake]Slang, Hist.
n. See 1865 quote.
1854  (1956)  I had a charming muffin yesterday. She is engaged to be married, so don't be alarmed.
1865  The fair Canadians may have been too kind in accepting the name and position of "muffins" from the young Britishry; but the latter cannot say that they have suffered much in consequence. A muffin is simply a lady who sits beside the male occupant of the sleighÂ--sola cum solo.
1873  We were then told that the term "muffin" is not in good odour at the present day; that no lady will admit she ever was or ever could be a muffin. . . . No lady owned to ever having been a muffin, at least not until she knew her young man well enough to tell him so.
1965  . . . at the beginning of the winter season each young man chose "a muffin"--a "steady date" for the season--an arrangement terminated by mutual consent in the following spring. . . .