And also, Pixiv says both futanari and trap. Neither are artist's tags so there's no way of taking on more seriously than the other. In the image it's a response to, it is definitely a trap, though. I asked the artist, I wonder if he'll respond.
Ah, well as I said, the image this is responding to is genderswap, and there's little chance that this artist thought otherwise because the picture in question is by an artist whose work is almost all genderswap (female to male), yaoi and yaoi shota. It's not all that, but most of it is, and there's no futa at all.