Lee at 20:51:23 6/3/98 from c445-40.svdcc.fju.edu.tw
In this poem, the flea is a metaphor, and I think the flea may be a temple which people won't go into easily. The speaker persuaded the lady to go the bed with him, but the lady refused to have sex with him. He said that the flea sucked both of them, so their blood has mixed together in the flea's body. The laud wanted to kill the flea, but the speaker said if she killed the flea, and she would kill three lives including the speaker, the mistress, and the flea.
In my opinion, if the lady wanted to have sex with the speaker, she still couldn't do it, because the surrounding didn't allow her to do it. Hence, if she did, she would be punished. Women are always limited to do something, but men can do what they want to do. Women will be scolded if they have sex with men without marriage, but men won't. In this sentence "And pampered swells with one blood made of two", when the flea kept on sucking, it would become pregnant.
"A sin, or shame, or loss of maidenhead," "Yet this enjoys before it woo" , though the speaker said it's unimportant, it did mean something. At first, the speaker didn't wanted the lady to kill the flea, but he said that if you killed the flea, you didn't lose anything, so I think it is quite tricky. What the speaker said is to persuade the lady to have sex with him.