1. Dark Lady Sonnets

2. The Dark Lady sequence (sonnets 127–152), distinguishes itself from the Fair Youth sequence by being overtly sexual in its passion.
Though the term is not used in any of the sonnets, the name has stuck since the women is described as having both dark features and having a dark nature. 
As with the Fair Youth, there have been many attempts to identify her with a real historical individual. Mary Fitton, Emilia Lanier and others have been suggested.

3. The Sonnet Speaker makes no bones about having a full out sexual affair with a married woman.  He is fully in love, hating her darker and less attractive qualities and despising himself for constantly staying with her even though he realizes how toxic their relationship is.

4. The sonnets offer to…
his wife , Anne Hathaway. Though their relationship may never have been very close, he imparts that she may have been the reason that he went to London to begin his acting and writing career and 'saved my life ' as he writes, in the process.  
Emilia Bassano Lanier,  a fiery woman with several connections to Shakespeare. A woman who is dark in complexion and eyes, musically inclined, unscrupulous and married, the most convincing woman possessing these myriad qualities.

5. Sonnets of William Shakespeare Sonnet 144
Two loves I have of comfort and despair, Which like two spirits do suggest me still: The better angel is a man right fair, The worser spirit a woman colour'd ill. To win me soon to hell, my female evil Tempteth my better angel from my side, And would corrupt my saint to be a devil, Wooing his purity with her foul pride. And whether that my angel be turn'd fiend Suspect I may, but not directly tell; But being both from me, both to each friend, I guess one angel in another's hell: Yet this shall I ne'er know, but live in doubt, Till my bad angel fire my good one out.