Not-a-tomato weed

This is not a tomato. It is a weed that sprouted up, with four of its brethren, in a pot I planted three wisteria seeds in several weeks ago. (The wisteria have just now started to come up–you can see one behind the weed.) I left this one just to see what it is. It’s in my pantry window, which is north-facing, but the neighbor’s house is white and I guess it gets enough light, because it’s doing as well or better than my tomato plants (which are starting to complain of the lack of water they’re getting in those tiny pots). I even pinched off one of the wisteria that, unfortunately, came up about a millimeter away from this weed because now I want it to grow so I can see what it is.

I don’t know of any tomato lookalikes (not that this says much). Maybe it is a tomato, but then it’s put in the existential conundrum of also being a weed, because it planted itself where I didn’t want it.  On the other hand, you could call it a bona fide plant since I want it to live and I’m trying to help it grow. What does that make it? I don’t know. But it’s green and growing, and once some of my other plants go outside I’m either going to send it to join them or put it in a sunny window to see what it can do when I let it loose.