Help sexing

[Simland]

Hi,

I was wondering if anyone could help me sex this Thamnophis sirtalis. To me, the tale looks like it's tapering steadily right from the cloaca. However, I thought the same thing for my other garter and I was told he's a male. Which has pretty much been confirmed by the fact that he has stopped growing and is nowhere near the size of a full grown female.

The taper on this one's tale, is very subtle, whether or not it actually starts at the cloaca, which makes it hard for me to be certain either way.

Its body is a bit on the thick side, which makes me think female, but it isn't thick enough for me to say that it's definitely one.

Also, don't be fooled by the thickness of the body where the last two fingers of my right hand are, on the second picture. That's a food lump.

What do you guys think? Youngish female or oldish make?