Tarantulas does notice, the sudden presence between his legs making him gasp and twitch in surprise. Ryja warned him, when they spoke of this before, but he wasn't expecting the change to be so...so sudden.

...He rocks his hips experimentally, with a careful eye on Ryja's face to see if it displeases her. Primus, the size of her...and she's already so hard. Tarantulas bites his own lower lip in a needy little moan.