^Heh. I'm doing a TOS watch with friends and we just covered that one about a week ago. Kirk and Miri together is pretty creepy even if she is the older woman.
At least, it's creepy if you decide to read into the dialog more than was likely intended.
Well, Miri's the one making romantic advances on Kirk, a teenager (psychologically) with a crush on an older man. Kirk's focused on, you know, not dying and all, so his flattery of Miri is just in the vein of trying to make her feel good about herself -- because to a '60s man (or a 2260s man written by a 1960s writer), the way to build a woman's confidence is to tell her she's physically desirable and will make a good wife for somebody someday.
I mean, let's not forget that Janice Rand also throws herself at Kirk and he rebuffs her advances. Again, first-season Kirk was about duty above all, nothing like the womanizing stereotype he's saddled with in pop culture, or like the more conventional, womanizing action hero he became to a greater extent in seasons 2 & 3.