Assuming that God made pairs of every animal, He already had the male/female idea in mind.
Why do you suppose that He didn’t make humans as a pair at first?
And on what day do you think Eve was created?
Here are the relevant passages:
Genesis 1:26-28, 31, 2:1-3
26 Then God said, “Let us make man in our image, in our likeness, and let them rule…”
27 So God created man in his own image,
in the image of God he created him;
male and female he created them.
28 God blessed them and said to them, “Be fruitful and increase in number; fill the earth and subdue it. 31 God saw all that he had made, and it was very good. And there was evening, and there was morning—the sixth day.
1 Thus the heavens and the earth were completed in all their vast array. 2 By the seventh day God had finished the work he had been doing; so on the seventh day he rested from all his work. 3 And God blessed the seventh day and made it holy, because on it he rested from all the work of creating that he had done.
Genesis 2:4-7, 15, 18, 20-22
4 This is the account of the heavens and the earth when they were created. When the LORD God made the earth and the heavens- 5 and no shrub of the field had yet appeared on the earth and no plant of the field had yet sprung up, for the LORD God had not sent rain on the earth and there was no man to work the ground, 6 but streams came up from the earth and watered the whole surface of the ground- 7 the LORD God formed the man from the dust of the ground and breathed into his nostrils the breath of life, and the man became a living being.
15 The LORD God took the man and put him in the Garden of Eden to work it and take care of it. 18 The LORD God said, “It is not good for the man to be alone. I will make a helper suitable for him.” 20 So the man gave names to all the livestock, the birds of the air and all the beasts of the field. But for Adam no suitable helper was found.
21 So the LORD God caused the man to fall into a deep sleep; and while he was sleeping, he took one of the man’s ribs and closed up the place with flesh. 22 Then the LORD God made a woman from the rib he had taken out of the man, and he brought her to the man.